Amaury Denoyelle [Mon, 11 Jan 2021 08:21:52 +0000 (09:21 +0100)]
MEDIUM: connection: protect idle conn lists with locks
This is a preparation work for connection reuse with sni/proxy
protocol/specific src-dst addresses.
Protect every access to idle conn lists with a lock. This is currently
strictly not needed because the access to the list are made with atomic
operations. However, to be able to reuse connection with specific
parameters, the list storage will be converted to eb-trees. As this
structure does not have atomic operation, it is mandatory to protect it
with a lock.
For this, the takeover lock is reused. Its role was to protect during
connection takeover. As it is now extended to general idle conns usage,
it is renamed to idle_conns_lock. A new lock section is also
instantiated named IDLE_CONNS_LOCK to isolate its impact on performance.
Amaury Denoyelle [Thu, 28 Jan 2021 09:16:29 +0000 (10:16 +0100)]
BUG/MINOR: backend: hold correctly lock when killing idle conn
The wrong lock seems to be held when trying to remove another thread
connection if max fd limit has been reached (locking the current thread
instead of the target thread lock).
CLEANUP: queue: Remove useless tests on p or pp in pendconn_process_next_strm()
This patch removes unecessary tests on p or pp pointers in
pendconn_process_next_strm() function. This should make cppcheck happy and
avoid false report of null pointer dereference.
Ilya Shipitsin [Wed, 10 Feb 2021 08:03:30 +0000 (13:03 +0500)]
CLEANUP: remove unused variable assigned found by Coverity
this is pure cleanup, no need to backport
2116 if ((end - 1) == (payload + strlen(PAYLOAD_PATTERN))) {
2117 /* if the payload pattern is at the end */
2118 s->pcli_flags |= PCLI_F_PAYLOAD;
CID 1399833 (#1 of 1): Unused value (UNUSED_VALUE)assigned_value: Assigning value from reql to ret here, but that stored value is overwritten before it can be used.
2119 ret = reql;
2120 }
BUG/MINOR: tools: Fix a memory leak on error path in parse_dotted_uints()
When an invalid character is found during parsing in parse_dotted_uints()
function, the allocated array of uint must be released. This patch fixes a
memory leak on error path during the configuration parsing.
This patch should fix the issue #1106. It should be backported as far as
2.0. Note that, for 2.1 and 2.0, the function is in src/standard.c
CLEANUP: muxes: Remove useless calls to b_realign_if_empty()
In H1, H2 and FCGI muxes, b_realign_if_empty() is called to reset the head
of an empty buffer before setting it a specific value to permit the
zero-copy. Thus, we can remove call to b_realign_if_empty().
William Dauchy [Mon, 8 Feb 2021 22:53:29 +0000 (23:53 +0100)]
BUG/MINOR: server: re-align state file fields number
Since commit 3169471964fdc49963e63f68c1fd88686821a0c4 ("MINOR: Add
server port field to server state file.") max_fields was not increased
on version number 1. So this patch aims to fix it. This should be
backported as far as v1.8, but the numbering should be adpated depending
on the version: simply increase the field by 1.
MINOR: mux-h1: Be sure EOM flag is set when processing end of outgoing message
When a message is sent, an extra check is performed when the parser is
switch to MSG_DONE state to be sure the EOM flag is really set. This flag is
quite new and replaces the EOM block. Thus, this test is a safeguard waiting
for a proper refactoring of the outgoing side.
BUG/MEDIUM: mux-h2: Add EOT block when EOM flag is set on an empty HTX message
In the H2 mux, when a empty DATA frame is used to finish a message, just to
set the ES flag, we now only set the EOM flag on the HTX message. However,
if the HTX message is empty, this event will not be properly handled on the
other side because there is no effective data to handle. Thus, it is
interpreted as an abort by the H1 mux.
It is in part caused by the current H1 mux design but also because there is
no way to emit empty HTX block (NOOP HTX block) or to wakeup a mux for send
when there is no data to finish some internal processing.
Thus, for now, to work around this limitation, an EOT HTX block is added by
the H2 mux if a EOM flag is added on an empty HTX message. This case is only
possible when an empty DATA frame with the ES flag is received.
BUG/MINOR: mux-h1: Don't blindly skip EOT block for non-chunked messages
In HTTP/2, we may have trailers for messages with a Content-length
header. Thus, when the H2 mux receives a HEADERS frame at the end of a
message, it always emits TLR and EOT HTX blocks. On the H1 mux, if this
happens, these blocks are just skipped because we cannot emit trailers for a
non-chunked message. But the EOT HTX block must not be blindly
ignored. Indeed, there is no longer EOM HTX block to mark the end of the
message. Thus the EOT block, when found, is the end of the message. So we
must handle it to swith in MSG_DONE state.
BUG/MINOR: mux-h1: Fix data skipping for bodyless responses
When payload is received for a bodyless response, for instance a response to
a HEAD request, it is silently skipped. Unfortunately, when this happens,
the end of the message is not properly handled. The response remains in the
MSG_DATA state (or MSG_TRAILERS if the message is chunked). In addition,
when a zero-copy is possible, the data are not removed from the channel
buffer and the H1 connection is killed because an error is then triggered.
To fix the bug, the zero-copy is disabled for bodyless responses. It is not
a problem because there is no copy at all. And the last block (DATA or EOT)
is now properly handled.
This bug was introduced by the commit e5596bf53 ("MEDIUM: mux-h1: Don't emit
any payload for bodyless responses").
BUG/MEDIUM: mux-h1: Always set CS_FL_EOI for response in MSG_DONE state
During the message parsing, if in MSG_DONE state, the CS_FL_EOI flag must
always be set on the conn-stream if following conditions are met :
* It is a response or
* It is a request but not a protocol upgrade nor a CONNECT.
For now, there is no test on the message type (request or response). Thus
the CS_FL_EOI flag is not set for a response with a "Connection: upgrade"
header but not a 101 response.
This bug was introduced by the commit 3e1748bbf ("BUG/MINOR: mux-h1: Don't
set CS_FL_EOI too early for protocol upgrade requests"). It was backported
as far as 2.0. Thus, this patch must also be backported as far as 2.0.
BUG/MINOR: http-ana: Don't increment HTTP error counter on internal errors
If internal error is reported by the mux during HTTP request parsing, the
HTTP error counter should not be incremented. It should only be incremented
on parsing error to reflect errors caused by clients.
This patch must be backported as far as 2.0. During the backport, the same
must be performed for 408-request-time-out errors.
Willy Tarreau [Wed, 10 Feb 2021 11:07:15 +0000 (12:07 +0100)]
MINOR: stick-tables/counters: add http_fail_cnt and http_fail_rate data types
Historically we've been counting lots of client-triggered events in stick
tables to help detect misbehaving ones, but we've been missing the same on
the server side, and there's been repeated requests for being able to count
the server errors per URL in order to precisely monitor the quality of
service or even to avoid routing requests to certain dead services, which
is also called "circuit breaking" nowadays.
This commit introduces http_fail_cnt and http_fail_rate, which work like
http_err_cnt and http_err_rate in that they respectively count events and
their frequency, but they only consider server-side issues such as network
errors, unparsable and truncated responses, and 5xx status codes other
than 501 and 505 (since these ones are usually triggered by the client).
Note that retryable errors are purposely not accounted for, so that only
what the client really sees is considered.
With this it becomes very simple to put some protective measures in place
to perform a redirect or return an excuse page when the error rate goes
beyond a certain threshold for a given URL, and give more chances to the
server to recover from this condition. Typically it could look like this
to bypass a URL causing more than 10 requests per second:
stick-table type string len 80 size 4k expire 1m store http_fail_rate(1m)
http-request track-sc0 base # track host+path, ignore query string
http-request return status 503 content-type text/html \
lf-file excuse.html if { sc0_http_fail_rate gt 10 }
A more advanced mechanism using gpt0 could even implement high/low rates
to disable/enable the service.
Reg-test converteers_ref_cnt_never_dec.vtc was updated to test it.
Willy Tarreau [Tue, 9 Feb 2021 16:39:08 +0000 (17:39 +0100)]
BUG/MINOR: freq_ctr: fix a wrong delay calculation in next_event_delay()
The sleep time calculation in next_event_delay() was wrong because it
was dividing 999 by the number of pending events, and was directly
responsible for an observation made a long time ago that listeners
would eat all the CPU when hammered while globally rate-limited,
because the more the queued events, the least it would wait, and would
ignore the configured frequency to compute the delay.
This was addressed in various ways in listeners through the switch to
the FULL state and the wakeup of manage_global_listener_queue() that
avoids this fast loop, but the calculation made there remained wrong
nevertheless. It's even visible with this patch that the accept
frequency is much more accurate at low values now; for example,
configuring a maxconrate of 10 would give between 8.99 and 11.0 cps
before this patch and between 9.99 and 10.0 with it.
Better fix it now in case it's reused anywhere else and causes confusion
again. It maybe be backported but is probably not worth it.
Willy Tarreau [Tue, 9 Feb 2021 16:10:54 +0000 (17:10 +0100)]
BUG/MINOR: intops: fix mul32hi()'s off-by-one
mul32hi() multiples a constant a with a variable b from 0 to 0xffffffff
and shifts the result by 32 bits. It's visible that it's always impossible
to reach the constant a this way because the product always misses exactly
one unit of a to be preserved. And this cannot be corrected by the caller
either as adding one to the output will only shift the output range, and
it's not possible to pass 2^32 on the ratio <b>. The right approach is to
add "a" after the multiplication so that the input range is always
preserved for all ratio values from 0 to 0xffffffff:
This is only used in freq_ctr calculations and the slightly lower value
is unlikely to have ever been noticed by anyone. This may be backported
though it is not important.
MEDIUM: ssl: add a rwlock for SSL server session cache
When adding the server side support for certificate update over the CLI
we encountered a design problem with the SSL session cache which was not
locked.
Indeed, once a certificate is updated we need to flush the cache, but we
also need to ensure that the cache is not used during the update.
To prevent the use of the cache during an update, this patch introduce a
rwlock for the SSL server session cache.
In the SSL session part this patch only lock in read, even if it writes.
The reason behind this, is that in the session part, there is one cache
storage per thread so it is not a problem to write in the cache from
several threads. The problem is only when trying to write in the cache
from the CLI (which could be on any thread) when a session is trying to
access the cache. So there is a write lock in the CLI part to prevent
simultaneous access by a session and the CLI.
This patch also remove the thread_isolate attempt which is eating too
much CPU time and was not protecting from the use of a free ptr in the
session.
Ilya Shipitsin [Mon, 8 Feb 2021 11:55:06 +0000 (16:55 +0500)]
BUILD: ssl: guard SSL_CTX_set_msg_callback with SSL_CTRL_SET_MSG_CALLBACK macro
both SSL_CTX_set_msg_callback and SSL_CTRL_SET_MSG_CALLBACK defined since ea262260469e49149cb10b25a87dfd6ad3fbb4ba, we can safely switch to that guard
instead of OpenSSL version
William Dauchy [Sun, 7 Feb 2021 19:42:38 +0000 (20:42 +0100)]
MEDIUM: contrib/prometheus-exporter: export base stick table stats
I saw some people falling back to unix socket to collect some data they
could not find in prometheus exporter. One of them is base info from
stick tables (used/size).
I do not plan to extend it more for now; keys are quite a mess to
handle.
William Dauchy [Sun, 7 Feb 2021 19:42:37 +0000 (20:42 +0100)]
MINOR: contrib/prometheus-exporter: use stats desc when possible followup
Remove remaining descrition which are common to stats.c.
This patch is a followup of commit 82b2ce2f967d967139adb7afab064416fadad615 ("MINOR:
contrib/prometheus-exporter: use stats desc when possible"). I probably
messed up with one of my rebase because I'm pretty sure I removed them
at some point, but who knows what happened.
BUG/MINOR: mux-h1: Don't emit extra CRLF for empty chunked messages
Because of a buggy tests when processing the EOH HTX block, an extra CRLF is
added for empty chunked messages. This bug was introduced by the commit d1ac2b90c ("MAJOR: htx: Remove the EOM block type and use HTX_FL_EOM
instead").
Ilya Shipitsin [Sat, 6 Feb 2021 13:59:22 +0000 (18:59 +0500)]
BUILD: ssl: guard SSL_CTX_add_server_custom_ext with special macro
special guard macros HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT was defined earlier
exactly for guarding SSL_CTX_add_server_custom_ext, let us use it wherever
appropriate
Ilya Shipitsin [Sat, 6 Feb 2021 13:55:27 +0000 (18:55 +0500)]
BUILD: ssl: fix typo in HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT macro
HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT was introduced in ec609098718b9c1cd803ca57442b2b98c9ba4a16
however it was defined as HAVE_SL_CTX_ADD_SERVER_CUSTOM_EXT (missing "S")
let us fix typo
Willy Tarreau [Fri, 5 Feb 2021 14:17:33 +0000 (15:17 +0100)]
[RELEASE] Released version 2.4-dev7
Released version 2.4-dev7 with the following main changes :
- BUG/MINOR: stats: Continue to fill frontend stats on unimplemented metric
- BUILD: ssl: guard Client Hello callbacks with HAVE_SSL_CLIENT_HELLO_CB macro instead of openssl version
- BUG/MINOR: stats: Init the metric variable when frontend stats are filled
- MINOR: contrib/prometheus-exporter: better output of Not-a-Number
- CLEANUP: stats: improve field selection for frontend http fields
- CLEANUP: assorted typo fixes in the code and comments
- DOC: Improve documentation of the various hdr() fetches
- MEDIUM: stats: allow to select one field in `stats_fill_be_stats`
- MINOR: contrib/prometheus-exporter: use fill_be_stats for backend dump
- MEDIUM: stats: allow to select one field in `stats_fill_sv_stats`
- MINOR: contrib/prometheus-exporter: use fill_sv_stats for server dump
- MINOR: abort() on my_unreachable() when DEBUG_USE_ABORT is set.
- BUG/MEDIUM: filters/htx: Fix data forwarding when payload length is unknown
- BUG/MINOR: config: fix leak on proxy.conn_src.bind_hdr_name
- MINOR: reg-tests: add http-reuse test
- CLEANUP: srv: fix comment for pool-max-conn
- CLEANUP: backend: remove an obsolete comment on conn_backend_get
- REORG: backend: simplify conn_backend_get
- MINOR: ssl: Server ssl context prepare function refactoring
- MINOR: ssl: Certificate chain loading refactorization
- MEDIUM: ssl: Load client certificates in a ckch for backend servers
- MEDIUM: ssl: Enable backend certificate hot update
- MINOR: ssl: Remove client_crt member of the server's ssl context
- CLEANUP: ssl/cli: rework free in cli_io_handler_commit_cert()
- CLEANUP: ssl: remove SSL_CTX function parameter
- CLEANUP: ssl: make load_srv_{ckchs,cert} match their bind counterpart
- BUILD: Include stdlib.h in compiler.h if DEBUG_USE_ABORT is set
- CI: Fix DEBUG_STRICT definition for Coverity
- BUG/MINOR: stats: Remove a break preventing ST_F_QCUR to be set for servers
- BUG/MINOR: stats: Add a break after filling ST_F_MODE field for servers
- CLEANUP: ssl: remove dead code in ckch_inst_new_load_srv_store()
- BUG/MINOR: ssl: init tmp chunk correctly in ssl_sock_load_sctl_from_file()
- BUG/MEDIUM: session: only retrieve ready idle conn from session
- BUG/MEDIUM: backend: never reuse a connection for tcp mode
- REGTESTS: set_ssl_server_cert.vtc: remove the abort command
- REGTESTS: set_ssl_server_cert.vtc: check the Sha1 Fingerprint
- REGTESTS: set_ssl_server_cert.vtc: check the sha1 from the server
- MEDIUM: stream-int: Take care of EOS if the SI wake callback function
- MINOR: mux-h1: Try to wake up data layer first before calling its wake callback
- MINOR: mux-h1: Wake up H1C after its creation if input buffer is not empty
- MEDIUM: mux-h1: Add ST_READY state for the H1 connections
- MINOR: stream: Add a function to validate TCP to H1 upgrades
- MEDIUM: http-ana: Do nothing in wait-for-request analyzer if not htx
- BUG/MEDIUM: stream: Don't immediatly ack the TCP to H1 upgrades
- BUG/MAJOR: mux-h1: Properly handle TCP to H1 upgrades
- MINOR: htx/http-ana: Save info about Upgrade option in the Connection header
- MEDIUM: http-ana: Refuse invalid 101-switching-protocols responses
- BUG/MINOR: h2/mux-h2: Reject 101 responses with a PROTOCOL_ERROR h2s error
- MINOR: mux-h1/mux-fcgi: Don't set TUNNEL mode if payload length is unknown
- MINOR: mux-h1: Split H1C_F_WAIT_OPPOSITE flag to separate input/output sides
- MINOR: mux-h2: Add 2 flags to help to properly handle tunnel mode
- MEDIUM: mux-h2: Block client data on server side waiting tunnel establishment
- MEDIUM: mux-h2: Close streams when processing data for an aborted tunnel
- MEDIUM: mux-h1: Properly handle tunnel establishments and aborts
- BUG/MAJOR: mux-h1/mux-h2/htx: Fix HTTP tunnel management at the mux level
- MINOR: htx: Rename HTX_FL_EOI flag into HTX_FL_EOM
- REGTESTS: Don't run http_msg_full_on_eom script on the 2.4 anymore
- MINOR: htx: Add a function to know if a block is the only one in a message
- MAJOR: htx: Remove the EOM block type and use HTX_FL_EOM instead
- MINOR: mux-h1: Add a flag on H1 streams with a response known to be bodyless
- MEDIUM: mux-h1: Don't emit any payload for bodyless responses
- MINOR: mux-h1: Don't emit C-L and T-E headers for 204 and 1xx responses
- MINOR: mux-h1: Don't add Connection close/keep-alive header for 1xx messages
- MINOR: h2/mux-h2: Add flags to notify the response is known to have no body
- MEDIUM: mux-h2: Don't emit DATA frame for bodyless responses
- MEDIUM: http-ana: Deal with L7 retries in HTTP analysers
- MINOR: h1: reject websocket handshake if missing key
- MEDIUM: h1: generate WebSocket key on response if needed
- MINOR: mux_h2: define H2_SF_EXT_CONNECT_SENT stream flag
- MEDIUM: h2: parse Extended CONNECT reponse to htx
- MEDIUM: mux_h2: generate Extended CONNECT from htx upgrade
- MEDIUM: h1: add a WebSocket key on handshake if needed
- MEDIUM: mux_h2: generate Extended CONNECT response
- MEDIUM: h2: parse Extended CONNECT request to htx
- MEDIUM: h2: send connect protocol h2 settings
- MINOR: vtc: add test for h1/h2 protocol upgrade translation
- MINOR: vtc: add websocket test
- REGTESTS: Fix required versions for several scripts
- REGTEST: Don't use the websocket to validate http-check
- MINOR: mux-h1/trace: add traces at level ERROR for all kind of errors
- MINOR: mux-fcgi/trace: add traces at level ERROR for all kind of errors
- MINOR: h1: Raise the chunk size limit up to (2^52 - 1)
- BUG/MEDIUM: listener: do not accept connections faster than we can process them
- REGTESTS: set_ssl_server_cert.vtc: set as broken
- Revert "BUG/MEDIUM: listener: do not accept connections faster than we can process them"
- BUG/MINOR: backend: check available list allocation for reuse
- CI: Fix the coverity builds
- DOC: management: fix "show resolvers" alphabetical ordering
- MINOR: tools: add print_time_short() to print a condensed duration value
- MINOR: activity: make profiling more manageable
- MINOR: activity: declare a new structure to collect per-function activity
- MEDIUM: tasks/activity: collect per-task statistics when profiling is enabled
- MINOR: activity: also report collected tasks stats in "show profiling"
- MINOR: activity: flush scheduler stats on "set profiling tasks on"
- MINOR: activity: add a new "show tasks" command to list currently active tasks
- MINOR: listener: export accept_queue_process
- MINOR: session: export session_expire_embryonic()
- MINOR: muxes: export the timeout and shutr task handlers
- MINOR: checks: export a few functions that appear often in trace dumps
- MINOR: peers: export process_peer_sync() to improve traces
- MINOR: stick-tables: export process_table_expire()
- MINOR: mux-h1: Remove first useless test on count in h1_process_output()
- BUG/MINOR: stick-table: Always call smp_fetch_src() with a valid arg list
- MINOR: http-fetch: Don't check if argument list is set in sample fetches
- MINOR: http-conv: Don't check if argument list is set in sample converters
- MINOR: sample: Don't check if argument list is set in sample fetches
- MINOR: ssl-sample: Don't check if argument list is set in sample fetches
- MINOR: mux-h2: Don't tests the start-line when sending HEADERS frame
- MINOR: mux-h2: Slightly improve request HEADERS frames sending
- MINOR: contrib/prometheus-exporter: declare states for objects
- MAJOR: contrib/prometheus-exporter: move ftd/bkd/srv states to labels
- MEDIUM: contrib/prometheus-exporter: Use dynamic labels instead of static ones
- MINOR: listener: export manage_global_listener_queue()
- BUG/MINOR: activity: take care of late wakeups in "show tasks"
- REGTESTS: set_ssl_server_cert.vtc: remove SSL caching and set as working
- REGTESTS: set_ssl_server_cert: cleanup the SSL caching option
- MINOR: checks: Add function to get the result code corresponding to a status
- MAJOR: contrib/prometheus-exporter: move health check status to labels
- MINOR: contrib/prometheus-exporter: improve service status description field
- MINOR: stats: improve pending connections description
- MINOR: stats: improve max stats descriptions
- MINOR: contrib/prometheus-exporter: use stats desc when possible
- MINOR: contrib/prometheus-exporter: add uweight field
- MINOR: contrib/prometheus-exporter: add recv logs_logs_total field
- CLEANUP: contrib/prometheus-exporter: remove unused includes
- CLEANUP: contrib/prometheus-exporter: align and reorder fields
- CLEANUP: contrib/prometheus-exporter: remove description in README
- DOC: contrib/prometheus-exporter: Add missing metrics in README
- BUG/MINOR: contrib/prometheus-exporter: Add missing label for ST_F_HRSP_1XX
- BUG/MINOR: contrib/prometheus-exporter: Restart labels dump at the right pos
- BUG/MEDIUM: ssl/cli: abort ssl cert is freeing the old store
- BUG/MEDIUM: ssl: check a connection's status before computing a handshake
- BUG/MINOR: mux_h2: fix incorrect stat titles
- MINOR: ssl/cli: flush the server session cache upon 'commit ssl cert'
- BUG/MINOR: cli: fix set server addr/port coherency with health checks
- MINOR: server: Don't set the check port during the update from a state file
- MINOR: dns: Don't set the check port during a server dns resolution
- MEDIUM: check: remove checkport checkaddr flag
- MEDIUM: server: adding support for check_port in server state
- BUG/MINOR: check: consitent way to set agentaddr
- MEDIUM: check: align agentaddr and agentport behaviour
- DOC: server: Add missing params in comment of the server state line parsing
- BUG/MINOR: xxhash: make sure armv6 uses memcpy()
- REGTESTS: mark http-check-send.vtc as 2.4-only
- REGTESTS: mark sample_fetches/hashes.vtc as 2.4-only
- BUG/MINOR: ssl: do not try to use early data if not configured
- REGTESTS: unbreak http-check-send.vtc
- MINOR: cli/show_fd: report local and report ports when known
- BUILD: Makefile: move REGTESTST_TYPE default setting
- BUG/MEDIUM: mux-h2: handle remaining read0 cases
- CLEANUP: http-htx: Set buffer area to NULL instead of malloc(0)
- BUG/MINOR: sock: Unclosed fd in case of connection allocation failure
- BUG/MEDIUM: mux-h2: do not quit the demux loop before setting END_REACHED
Willy Tarreau [Fri, 5 Feb 2021 11:16:01 +0000 (12:16 +0100)]
BUG/MEDIUM: mux-h2: do not quit the demux loop before setting END_REACHED
The demux loop could quit on missing data but the H2_CF_END_REACHED flag
would not be set in this case. This fixes a remaining situation where
previous commit f09612289 ("BUG/MEDIUM: mux-h2: handle remaining read0
cases") could not be sufficient and still leave CLOSE_WAIT. It's harder
to reproduce but was still observed in prod.
Now we quit via the end of the loop which already takes care of shutr.
This should be backported along with the patch above as far as 2.0.
CLEANUP: http-htx: Set buffer area to NULL instead of malloc(0)
During error files conversion to HTX message, in http_str_to_htx(), if a
file is empty, the corresponding buffer's area is initialized with a
malloc(0) and its size is set to 0. There is no problem here. The behaviour
is totally defined. But it is not really intuitive. Instead, we can simply
set the area to NULL.
Willy Tarreau [Fri, 5 Feb 2021 10:41:46 +0000 (11:41 +0100)]
BUG/MEDIUM: mux-h2: handle remaining read0 cases
Commit 3d4631fec ("BUG/MEDIUM: mux-h2: fix read0 handling on partial
frames") tried to address an issue introduced in commit aade4edc1 where
read0 wasn't properly handled in the middle of a frame. But the fix was
incomplete for two reasons:
- first, it would set H2_CF_RCVD_SHUT in h2_recv() after detecting
a read0 but the condition was guarded by h2_recv_allowed() which
explicitly excludes read0 ;
- second, h2_process would only call h2_process_demux() when there
were still data in the buffer, but closing after a short pause to
leave a buffer empty wouldn't be caught in this case.
This patch fixes this by properly taking care of the received shutdown
and by also waking up h2_process_demux() on an empty buffer if the demux
is not blocked.
Given the patches above were tagged for backporting to 2.0, this one
should be as well.
In patch 3bad3d5 ("BUILD: Makefile: exclude broken tests by default"),
the default setting of the REGTESTST_TYPE variable was set in the
Makefile instead of the run-regtests.sh script.
Doing it in the Makefile was breaking the use of this environment
varible with make ( REGTESTS_TYPES=slow,default make reg-tests )
This patch move the default setting from the Makefile to
run-regtests.sh. It also change the documentation in `make
reg-tests-help` about the default value.
This patch should be backported where 3bad3d5 is backported.
Willy Tarreau [Fri, 5 Feb 2021 09:54:52 +0000 (10:54 +0100)]
MINOR: cli/show_fd: report local and report ports when known
FD dumps are not always easy to match against netstat dumps, and often
require an lsof as a third dump. Let's emit the socket family, and the
local and remore ports when the FD is an IPv4/IPv6 socket, this will
significantly ease the matching.
Willy Tarreau [Fri, 5 Feb 2021 09:13:15 +0000 (10:13 +0100)]
REGTESTS: unbreak http-check-send.vtc
As noticed by Christopher, I messed up the version fix in commit cb4ed02ef ("REGTESTS: mark http-check-send.vtc as 2.4-only"), as while
looking up the commit introducing the change I accidently reverted it.
Let's reinsert the contents of the file prior to that fix, except the
version, of course.
Willy Tarreau [Wed, 3 Feb 2021 10:21:38 +0000 (11:21 +0100)]
BUG/MINOR: ssl: do not try to use early data if not configured
The CO_FL_EARLY_SSL_HS flag was inconditionally set on the connection,
resulting in SSL_read_early_data() always being used first in handshake
calculations. While this seems to work well (probably that there are
fallback paths inside openssl), it's particularly confusing and makes
the debugging quite complicated. It possibly is not optimal by the way.
This flag ought to be set only when early_data is configured on the bind
line. Apparently there used to be a good reason for doing it this way in
1.8 times, but it really does not make sense anymore. It may be OK to
backport this to 2.3 if this helps with troubleshooting, but better not
go too far as it's unlikely to fix any real issue while it could introduce
some in old versions.
Willy Tarreau [Thu, 4 Feb 2021 17:07:59 +0000 (18:07 +0100)]
REGTESTS: mark sample_fetches/hashes.vtc as 2.4-only
Commit 9eea56009 ("REGTESTS: add tests for the xxh3 converter") introduced
the xxh3 to the tests thus made it incompatible with 2.3 and older, let's
upgrade the version requirement.
Willy Tarreau [Thu, 4 Feb 2021 16:02:39 +0000 (17:02 +0100)]
BUG/MINOR: xxhash: make sure armv6 uses memcpy()
There was a special case made to allow ARMv6 to use unaligned accesses
via a cast in xxHash when __ARM_FEATURE_UNALIGNED is defined. But while
ARMv6 (and v7) does support unaligned accesses, it's only for 32-bit
pointers, not 64-bit ones, leading to bus errors when the compiler emits
an ldrd instruction and the input (e.g. a pattern) is not aligned, as in
issue #1035.
Note that v7 was properly using the packed approach here and was safe,
however haproxy versions 2.3 and older use the old r39 xxhash code which
has the same issue for armv7. A slightly different fix is required there,
by using a different definition of packed for 32 and 64 bits.
The problem is really visible when running v7 code on a v8 kernel because
such kernels do not implement alignment trap emulation, and the process
dies when this happens. This is why in the issue above it was only detected
under lxc. The emulation could have been disabled on v7 as well by writing
zero to /proc/cpu/alignment though.
This commit is a backport of xxhash commit a470f2ef ("update default memory
access for armv6").
Thanks to @srkunze for the report and tests, @stgraber for his help on
setting up an easy reproducer outside of lxc, and @Cyan4973 for the
discussion around the best way to fix this. Details and alternate patches
available on https://github.com/Cyan4973/xxHash/issues/490.
William Dauchy [Wed, 3 Feb 2021 21:30:09 +0000 (22:30 +0100)]
MEDIUM: check: align agentaddr and agentport behaviour
in the same manner of agentaddr, we now:
- permit to set agentport through `port` keyword, like it is the case
for agentaddr through `addr`
- set the priority on `agent-port` keyword when used
- add a flag to be able to test when the value is set like for agentaddr
it makes the behaviour between `addr` and `port` more consistent.
William Dauchy [Wed, 3 Feb 2021 21:30:08 +0000 (22:30 +0100)]
BUG/MINOR: check: consitent way to set agentaddr
small consistency problem with `addr` and `agent-addr` options:
for the both options, the last one parsed is always used to set the
agent-check addr. Thus these two lines don't have the same behavior:
server ... addr <addr1> agent-addr <addr2>
server ... agent-addr <addr2> addr <addr1>
After this patch `agent-addr` will always be the priority option over
`addr`. It means we test the flag before setting agentaddr.
We also fix all the places where we did not set the flag to be coherent
everywhere.
I was not really able to determine where this issue is coming from. So
it is probable we may backport it to all stable version where the agent
is supported.
William Dauchy [Wed, 3 Feb 2021 21:30:06 +0000 (22:30 +0100)]
MEDIUM: server: adding support for check_port in server state
We can currently change the check-port using the cli command `set server
check-port` but there is a consistency issue when using server state.
This patch aims to fix this problem but will be also a good preparation
work to get rid of checkport flag, so we are able to know when checkport
was set by config.
I am fully aware this is not making github #953 moving forward, I
however think this might be acceptable while waiting for a proper
solution and resolve consistency problem faced with port settings.
William Dauchy [Wed, 3 Feb 2021 21:30:07 +0000 (22:30 +0100)]
MEDIUM: check: remove checkport checkaddr flag
While trying to fix some consistency problem with the config file/cli
(e.g. check-port cli command does not set the flag), we realised
checkport flag was not necessarily needed. Indeed tcpcheck uses service
port as the last choice if check.port is zero. So we can assume if
check.port is zero, it means it was never set by the user, regardless if
it is by the cli or config file. In the longterm this will avoid to
introduce a new consistency issue if we forget to set the flag.
in the same manner of checkport flag, we don't really need checkaddr
flag. We can assume if checkaddr is not set, it means it was never set
by the user or config.
MINOR: dns: Don't set the check port during a server dns resolution
When a server dns resolution is performed, there is no reason to set an
unconfigured check port with the server port. Because by default, if the
check port is not set, the server's one is used. Thus we can remove this
useless assignment. It is mandatory for next improvements.
MINOR: server: Don't set the check port during the update from a state file
When the server state is loaded from a server-state file, there is no reason
to set an unconfigured check port with the server port. Because by default,
if the check port is not set, the server's one is used. Thus we can remove
this useless assignment. It is mandatory for next improvements.
William Dauchy [Wed, 3 Feb 2021 21:30:05 +0000 (22:30 +0100)]
BUG/MINOR: cli: fix set server addr/port coherency with health checks
while reading `update_server_addr_port` I found out some things which
can be seen as incoherency. I hope I did not overlooked anything:
- one comment is stating check's address should be updated if it uses
the server one; however the condition checks if `SRV_F_CHECKADDR` is
set; this flag is set when a check address is set; result is that we
override the check address where I was not expecting it. In fact we
don't need to update anything here as server addr is used when check
addr is not set.
- same goes for check agent addr
- for port, it is a bit different, we update the check port if it is
unset. This is harmless because we also use server port if check port
is unset. However it creates some incoherency before/after using this
command, as check port should stay unset througout the life of the
process unless it is is set by `set server check-port` command.
quite hard to locate the origin of this this issue but the function was
introduced in commit d458adcc52b74608e2fe6a2a95f09ce5e94932b7 ("MINOR:
new update_server_addr_port() function to change both server's ADDR and
service PORT"). I was however not able to determine whether this is due
to a change of behavior along the years. So this patch can potentially
be backported up to v1.8 but we must be careful while doing so, as the
code has changed a lot. That being said, the bug being not very
impacting I would be fine keeping it for 2.4 only.
MINOR: ssl/cli: flush the server session cache upon 'commit ssl cert'
Flush the SSL session cache when updating a certificate which is used on a
server line. This prevent connections to be established with a cached
session which was using the previous SSL_CTX.
This patch also replace the ha_barrier with a thread_isolate() since there
are more operations to do. The reg-test was also updated to remove the
'no-ssl-reuse' keyword which is now uneeded.
Willy Tarreau [Tue, 2 Feb 2021 14:42:25 +0000 (15:42 +0100)]
BUG/MEDIUM: ssl: check a connection's status before computing a handshake
As spotted in issue #822, we're having a problem with error detection in
the SSL layer. The problem is that on an overwhelmed machine, accepted
connections can start to pile up, each of them requiring a slow handshake,
and during all this time if the client aborts, the handshake will still be
calculated.
The error controls are properly placed, it's just that the SSL layer
reads records exactly of the advertised size, without having the ability
to encounter a pending connection error. As such if injecting many TLS
connections to a listener with a huge backlog, it's fairly possible to
meet this situation:
12:50:48.257270 getsockopt(1109, SOL_SOCKET, SO_ERROR, [ECONNRESET], [4]) = 0
(proof that error was detectable there but this code was added for the PoC)
The situation was amplified by the multi-queue accept code, as it resulted
in many incoming connections to be accepted long before they could be
handled. Prior to this they would have been accepted and the handshake
immediately started, which would have resulted in most of the connections
waiting in the the system's accept queue, and dying there when the client
aborted, thus the error would have been detected before even trying to
pass them to the handshake code.
As a result, with a listener running on a very large backlog, it's possible
to quickly accept tens of thousands of connections and waste time slowly
running their handshakes while they get replaced by other ones.
This patch adds an SO_ERROR check on the connection's FD before starting
the handshake. This is not pretty as it requires to access the FD, but it
does the job.
Some improvements should be made over the long term so that the transport
layers can report extra information with their ->rcv_buf() call, or at the
very least, implement a ->get_conn_status() function to report various
flags such as shutr, shutw, error at various stages, allowing an upper
layer to inquire for the relevance of engaging into a long operation if
it's known the connection is not usable anymore. An even simpler step
could probably consist in implementing this in the control layer.
This patch is simple enough to be backported as far as 2.0.
Many thanks to @ngaugler for his numerous tests with detailed feedback.
BUG/MINOR: contrib/prometheus-exporter: Restart labels dump at the right pos
For some metrics, several lines are produced per entity, one per label
value. For instance, the health-check status (ST_F_CHECK_STATUS) or the
entity status (ST_F_STATUS). The dump may be stopped in the middle of the
labels processing if the output buffer is full. This means the next time, we
must take care to restart on the right label value.
For now, this part is buggy and we always restart to dump all the label
values again from the beginning. To be sure to restart at the right
position, the field <ctx.stats.st_code> in the applet context is used to
save the last position. Of course, we take care to reset this value when
necessary.
BUG/MINOR: contrib/prometheus-exporter: Add missing label for ST_F_HRSP_1XX
Since the labels are dynamically created for each metric, the "code" label
of the ST_F_HRSP_1XX field is missing. To fix the bug, this metric is
handled in the same way the other ST_F_HRSP_* field are. We only take care
to dump the metric header only once.
This bug was introduced by the commit 5a2f93873 ("MEDIUM:
contrib/prometheus-exporter: Use dynamic labels instead of static ones"). No
backport needed.
DOC: contrib/prometheus-exporter: Add missing metrics in README
Some metrics were missing (haproxy_process_uptime_seconds and
haproxy_process_build_info). To ease the review against the service output,
the same order is used in the README.
William Dauchy [Mon, 1 Feb 2021 12:12:00 +0000 (13:12 +0100)]
CLEANUP: contrib/prometheus-exporter: remove description in README
Now that we got ride of description in prometheus code, let's assume we
no longer need to maintain it in README, and diret user to the output of
prometheus to get more info.
William Dauchy [Mon, 1 Feb 2021 12:11:59 +0000 (13:11 +0100)]
CLEANUP: contrib/prometheus-exporter: align and reorder fields
- align safe_idle_connections_current field
fix minor typo added in commit 37286a5ac595069a491c3e8a7a7e4faf3d9ea8ad ("MEDIUM:
contrib/prometheus-exporter: Rework matrices defining Promex metrics")
- reorder info fields to be able to compare them easily
- add missing ignored info fields as comment
William Dauchy [Mon, 1 Feb 2021 12:11:58 +0000 (13:11 +0100)]
CLEANUP: contrib/prometheus-exporter: remove unused includes
unless I'm wrong, those includes are no longer needed. The only recent
one I remember is ssl-sock include since commit 5d9b8f3c9347a1a10b86f81d70b22c3cab0e6925 ("MINOR:
contrib/prometheus-exporter: use fill_info for process dump") where we
make use of the code from stats.c
William Dauchy [Mon, 1 Feb 2021 12:11:55 +0000 (13:11 +0100)]
MINOR: contrib/prometheus-exporter: use stats desc when possible
It is a followup work of commit a191b77e54c26a97064cb42ab4927d4f5c95b896
("MINOR: contrib/prometheus-exporter: merge info description from
stats") but for all other stats fields; we however keep a way to
override them when needed (e.g. units, specific cases)
this is another step which will avoid duplicating work between stats.c
and prometheus.
William Dauchy [Mon, 1 Feb 2021 12:11:54 +0000 (13:11 +0100)]
MINOR: stats: improve max stats descriptions
In order to unify prometheus and stats description, we need to remove
some field reference which are specific to stats implementation:
- `scur` in max current sessions (also reword current session)
- `rate` in max sessions
- `req_rate` in max requests
- `conn_rate` in max connections
In order to unify prometheus and stats description, we need to clarify
the description for pending connections.
- remove the BE reference in counters struct, as it is also used in
servers
- remove reference of `qcur` field in description as it is specific to
stats implemention
- try to reword cur and max pending connections description
William Dauchy [Mon, 1 Feb 2021 12:11:52 +0000 (13:11 +0100)]
MINOR: contrib/prometheus-exporter: improve service status description field
Since we changed the behaviour of this metric, improve the description
to better explain what is the meaning of the new gauge value; it also
reflects the description we did for health check status.
William Dauchy [Mon, 1 Feb 2021 12:11:51 +0000 (13:11 +0100)]
MAJOR: contrib/prometheus-exporter: move health check status to labels
this patch is a breaking change between v2.3 and v2.4: we move from
using gauge value for health check states to labels values. The diff is
quite small thanks to the preparation work from Christopher to allow
more flexibility in labels, see commit 5a2f938732126f43bbf4cea5482c01552b0d0314 ("MEDIUM:
contrib/prometheus-exporter: Use dynamic labels instead of static ones")
this is a follow up of commit c6464591a365bfcf509b322bdaa4d608c9395d75
("MAJOR: contrib/prometheus-exporter: move ftd/bkd/srv states to
labels"). The main goal being to be better aligned with prometheus use
cases in terms of queries. More specifically to health checks, Pierre C.
mentioned the possible quirks he had to put in place in order to make
use of those metrics through prometheus:
I am perfectly aware this introduces a lot more metrics but I don't see
how we can improve the usability without it. The main issue remains in
the cardinality of the states which are > 20. Prometheus recommends to
stay below a cardinality of 10 for a given metric but I consider our
case very specific, because highly linked to the level of precision
haproxy exposes.
Even before this patch I saw several large production setup (a few
hundreds of MB in output) which are making use of the scope parameter to
simply ignore the server metrics, so that the scrapping can be faster,
and memory consumed on client side not too high. So I believe we should
eventually continue in that direction and offer more granularity of
filtering of the output. That being said it is already possible to
filter out the data on prometheus client side.
MINOR: checks: Add function to get the result code corresponding to a status
The function get_check_status_result() can now be used to get the result
code (CHK_RES_*) corresponding to a check status (HCHK_STATUS_*). It will be
used by the Prometheus exporter when reporting the check status of a server.
REGTESTS: set_ssl_server_cert.vtc: remove SSL caching and set as working
In a previous commit this test was disabled because I though the
feature was broken, but in fact this is the test which is broken.
Indeed the connection between the server and the client was not
renegociated and was using the SSL cache or a ticket. To be work
correctly these 2 features must be disabled or a new connection must be
established after the ticket timeout, which is too long for a regtest.
Also a "nbthread 1" was added as it was easier to reproduce the problem
with it.
Willy Tarreau [Fri, 29 Jan 2021 14:04:16 +0000 (15:04 +0100)]
BUG/MINOR: activity: take care of late wakeups in "show tasks"
During the call to thread_isolate(), some other threads might have
performed some task_wakeup() which will have a call date past the
one we retrieved. It could be avoided by taking the current date
once we're alone but this would significantly affect the latency
measurements by adding the isolation time. Instead we're now only
accounting positive times, so that late wakeups normally appear
with a zero latency.
MEDIUM: contrib/prometheus-exporter: Use dynamic labels instead of static ones
Instead of using static labels for metrics, we now use an array of labels,
filled for each metrics if necessary and passed to the dump function. This
way, it is easier to extend the promex service. For now, there are at most 8
labels per metrics. This limit may be raised by changing PROMEX_MAX_LABELS
value. And to ease labels addition, a label is defined as a key/value
pair. The formatting is handled by the dump function.
For the proxies and servers, the first entry of the array is always the
proxy name. In addition, for the servers, the second entry is always the
server name.
William Dauchy [Wed, 27 Jan 2021 21:40:17 +0000 (22:40 +0100)]
MAJOR: contrib/prometheus-exporter: move ftd/bkd/srv states to labels
this patch is a breaking change between v2.3 and v2.4: we move from
using gauge value for frontend/backend/servers states to labels values.
the main motivation being I realised it is very difficult to make use of
it without hard coded quirks on prometheus client side; especially
because the main use is often to group by state, which is harder when
the state is the value of the metric.
in order to achieve that we iterate on the status metric to generate
labels, and so as many metrics.
this is the first step to resolve github issue #1029
A second step should address health check states.
In h2s_bck_make_req_headers() function, in the loop on the HTX blocks, the
most common blocks, the headers, are now handled in first, before the
start-line. The same change was already performed on the response HEADERS
frames. Thus the code is more consistent now.
MINOR: mux-h2: Don't tests the start-line when sending HEADERS frame
When a HEADERS frame is sent, it is always when an HTX start-line block is
found. Thus, in h2s_bck_make_req_headers() and h2s_frt_make_resp_headers()
functions, it is useless to tests the start-line. Instead of being too
defensive, we use BUG_ON() now because it must not happen and must be
handled as a bug.
MINOR: http-fetch: Don't check if argument list is set in sample fetches
The list is always defined by definition. Thus there is no reason to test
it. There is also plenty of checks on arguments types while it is already
validated during the configuration parsing. But one thing at a time.
BUG/MINOR: stick-table: Always call smp_fetch_src() with a valid arg list
The sample fetch functions must always be called with a valid argument
list. When called by hand, if there is no argument to pass, empty_arg_list must
be used.
In the stick-table code, there are some calls to smp_fetch_src() with NULL as
argument list. It is changed to use empty_arg_list instead. It is not really a
bug because smp_fetch_src() does not use the argument list. But it is an API
bug.
This patch may be backported to all stable branches as a cleanup.
MINOR: mux-h1: Remove first useless test on count in h1_process_output()
h1_process_output() function is never called with no data to send (count ==
0). Thus, the first test on count, at the beginning of the function is
useless and may be removed. This way, by reading the code, it is obvious the
<chn_htx> variable is always defined.
This handler can take quite some time as it deletes a large number of
entries under a lock, let's export it so that it's immediately visible
in "show profiling".
Willy Tarreau [Fri, 29 Jan 2021 11:35:24 +0000 (12:35 +0100)]
MINOR: checks: export a few functions that appear often in trace dumps
The check I/O handler, process_chk_conn and server_warmup are often
present in complex backtraces as they're impacted by locking or I/O
issues. Let's export them so that they resolve cleanly.
Willy Tarreau [Fri, 29 Jan 2021 10:32:55 +0000 (11:32 +0100)]
MINOR: activity: add a new "show tasks" command to list currently active tasks
This finally adds the long-awaited solution to inspect the run queues
and figure what is eating the CPU or causing latencies. We can even see
the experienced latencies when profiling is enabled. Example on a
saturated process:
Willy Tarreau [Fri, 29 Jan 2021 10:56:21 +0000 (11:56 +0100)]
MINOR: activity: flush scheduler stats on "set profiling tasks on"
If a user enables profiling by hand, it makes sense to reset the stats
counters to provide fresh new measurements. Therefore it's worth using
this as the standard method to reset counters.
Willy Tarreau [Thu, 28 Jan 2021 23:07:40 +0000 (00:07 +0100)]
MINOR: activity: also report collected tasks stats in "show profiling"
"show profiling" will now dump the stats collected by the scheduler if
profiling was previously enabled. This will immediately make it obvious
what functions are responsible for others' high latencies or which ones
are suffering from others, and should help spot issues like undesired
wakeups.
Willy Tarreau [Thu, 28 Jan 2021 23:07:40 +0000 (00:07 +0100)]
MEDIUM: tasks/activity: collect per-task statistics when profiling is enabled
Now when the profiling is enabled, the scheduler wlil update per-function
task-level statistics on number of calls, cpu usage and lateny, that could
later be checked using "show profiling". This will immediately make it
obvious what functions are responsible for others' high latencies or which
ones are suffering from others, and should help spot issues like undesired
wakeups. For now the stats are only collected but not reported (though they
are readable from sched_activity[] under gdb).
Willy Tarreau [Thu, 28 Jan 2021 18:19:26 +0000 (19:19 +0100)]
MINOR: activity: declare a new structure to collect per-function activity
The new sched_activity structure will be used to collect task-level
activity based on the target function. The principle is to declare a
large enough array to make collisions rare (256 entries), and hash
the function pointer using a reduced XXH to decide where to store the
stats. On first computation an entry is definitely assigned to the
array and it's done atomically. A special entry (0) is used to store
collisions ("others"). The goal is to make it easy and inexpensive for
the scheduler code to use these to store #calls, cpu_time and lat_time
for each task.
Willy Tarreau [Thu, 28 Jan 2021 20:44:22 +0000 (21:44 +0100)]
MINOR: activity: make profiling more manageable
In 2.0, commit d2d3348ac ("MINOR: activity: enable automatic profiling
turn on/off") introduced an automatic mode to enable/disable profiling.
The problem is that the automatic mode automatically changes to on/off,
which implied that the forced on/off modes aren't sticky anymore. It's
annoying when debugging because as soon as the load decreases, profiling
stops.
This makes a small change which ought to have been done first, which
consists in having two states for "auto" (auto-on, auto-off) to
distinguish them from the forced states. Setting to "auto" in the config
defaults to "auto-off" as before, and setting it on the CLI switches to
auto but keeps the current operating state.
This is simple enough to be backported to older releases if needed.
Willy Tarreau [Fri, 29 Jan 2021 09:47:52 +0000 (10:47 +0100)]
MINOR: tools: add print_time_short() to print a condensed duration value
When reporting some values in debugging output we often need to have
some condensed, stable-length values. This function prints a duration
from nanosecond to years with at least 4 digits of accuracy using the
most suitable unit, always on 7 chars.
It turns out that Coverity does not properly handle quoting within
`COVERITY_SCAN_BUILD_COMMAND`, instead breaking up single arguments at
whitespace, thus passing `-DDEBUG_USE_ABORT=1` to `make` as-is.
Fix this issue by hijacking the Makefile within the Coverity workflow. We
simply replace the default value of the `DEBUG` option with whatever values we
need. The build command now only includes the TARGET and USE_* flags, each of
which works without any spaces.
Amaury Denoyelle [Thu, 28 Jan 2021 16:33:26 +0000 (17:33 +0100)]
BUG/MINOR: backend: check available list allocation for reuse
Do not consider reuse connection if available list is not allocated for
the target server. This will prevent a crash when using a standalone
server for an external purpose like socket_tcp/socket_ssl on hlua code.
For the idle/safe lists, they are considered allocated if
srv.max_idle_conns is not null.
Note that the hlua code is currently safe thanks to the additional
checks on proxy http mode and stream reuse policy not never. However,
this might not be sufficient for future code.
This patch should be backported in every branches containing the
following patch : 7f68d815af356fbe1b2e1080a88b9935581c91d2 (2.4 tree)
REORG: backend: simplify conn_backend_get
While is works extremely well to address SSL handshake floods, it prevents
establishment of new connections during regular traffic above 50-60 Gbps,
because for an unknown reason the queue seems to have ~1.7 active tasks
per connection all the time, which makes no sense as these ought to be
waiting on subscribed events. It might uncover a deeper issue but at least
for now a different solution is needed. cf issue #822.
The test is trivial to run, just start a config with tune.runqueue-depth 10
and inject on 1GB objects with more than 10 connections. Try to connect to
the stats socket, it only works once, then the listeners are not dequeued.