From: Vito Caputo <vcaputo@pengaru.com>
Date: Sat, 21 Sep 2024 21:43:51 +0000 (-0700)
Subject: mmap-cache: add some stats about files/windows/unused
X-Git-Tag: v257-rc1~243^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=284802c597aa0194dc1504db65ee24941d9721eb;p=thirdparty%2Fsystemd.git

mmap-cache: add some stats about files/windows/unused

Let's give some visibility into the ratio of files:windows:unused
by the time we're done using the cache.
---

diff --git a/src/libsystemd/sd-journal/mmap-cache.c b/src/libsystemd/sd-journal/mmap-cache.c
index 249b98a968c..ce8aff3c5c1 100644
--- a/src/libsystemd/sd-journal/mmap-cache.c
+++ b/src/libsystemd/sd-journal/mmap-cache.c
@@ -435,8 +435,8 @@ found:
 void mmap_cache_stats_log_debug(MMapCache *m) {
         assert(m);
 
-        log_debug("mmap cache statistics: %u category cache hit, %u window list hit, %u miss",
-                  m->n_category_cache_hit, m->n_window_list_hit, m->n_missed);
+        log_debug("mmap cache statistics: %u category cache hit, %u window list hit, %u miss, %u files, %u windows, %u unused",
+                  m->n_category_cache_hit, m->n_window_list_hit, m->n_missed, hashmap_size(m->fds), m->n_windows, m->n_unused);
 }
 
 static void mmap_cache_process_sigbus(MMapCache *m) {
diff --git a/src/libsystemd/sd-journal/sd-journal.c b/src/libsystemd/sd-journal/sd-journal.c
index daa9670ab4c..858aeca45ef 100644
--- a/src/libsystemd/sd-journal/sd-journal.c
+++ b/src/libsystemd/sd-journal/sd-journal.c
@@ -2542,6 +2542,10 @@ _public_ void sd_journal_close(sd_journal *j) {
 
         sd_journal_flush_matches(j);
 
+        /* log stats before closing files so we can see the windows state */
+        if (j->mmap)
+                mmap_cache_stats_log_debug(j->mmap);
+
         ordered_hashmap_free_with_destructor(j->files, journal_file_close);
         iterated_cache_free(j->files_cache);
 
@@ -2553,10 +2557,8 @@ _public_ void sd_journal_close(sd_journal *j) {
 
         safe_close(j->inotify_fd);
 
-        if (j->mmap) {
-                mmap_cache_stats_log_debug(j->mmap);
+        if (j->mmap)
                 mmap_cache_unref(j->mmap);
-        }
 
         hashmap_free_free(j->errors);