From 011f7d77a378955129db7448ea628dea624a5732 Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Tue, 7 Jan 2003 22:22:27 +0100 Subject: [PATCH] version 2.1 release --- ccache.1 | 27 +++++++++++++++++++++++++++ web/ccache-man.html | 22 ++++++++++++++++++++++ web/index.html | 4 +++- 3 files changed, 52 insertions(+), 1 deletion(-) diff --git a/ccache.1 b/ccache.1 index 8bada69e1..24242391a 100644 --- a/ccache.1 +++ b/ccache.1 @@ -248,6 +248,33 @@ compiler output that you would get without the cache\&. If you ever discover a case where ccache changes the output of your compiler then please let me know\&. .PP +.SH "SHARING A CACHE" +.PP +A group of developers can increase the cache hit rate by sharing a +cache directory\&. The hard links however cause unwanted side effects, +as all links to a cached file share the file\&'s modification timestamp\&. +This results in false dependencies to be triggered by timestamp-based +build systems whenever another user links to an existing +file\&. Typically, users will see that their libraries and binaries are +relinked without reason\&. To share a cache without side effects, the +following conditions need to be met: +.PP +.IP o +Use the same \fBCCACHE_DIR\fP environment variable setting +.IP o +Set the \fBCCACHE_NOLINK\fP environment variable +.IP o +Make sure that all users have write permission in the entire +cache directory (and that you trust all users of the shared cache)\&. +.IP o +Tell your users to set a umask that allows group writes +(eg\&. umask 002) +.IP o +Make sure that the setgid bit is set on all directories in the +cache\&. This tells the filesystem to inherit group ownership for new +directories\&. The command "chmod g+s `find $CCACHE_DIR -type d`" might +be useful for this\&. +.PP .SH "HISTORY" .PP ccache was inspired by the compilercache shell script script written diff --git a/web/ccache-man.html b/web/ccache-man.html index c80dea509..3c606f137 100644 --- a/web/ccache-man.html +++ b/web/ccache-man.html @@ -198,6 +198,28 @@ all warnings etc) from the cache. compiler output that you would get without the cache. If you ever discover a case where ccache changes the output of your compiler then please let me know. +

SHARING A CACHE

+ +

A group of developers can increase the cache hit rate by sharing a +cache directory. The hard links however cause unwanted side effects, +as all links to a cached file share the file's modification timestamp. +This results in false dependencies to be triggered by timestamp-based +build systems whenever another user links to an existing +file. Typically, users will see that their libraries and binaries are +relinked without reason. To share a cache without side effects, the +following conditions need to be met: +

HISTORY

ccache was inspired by the compilercache shell script script written diff --git a/web/index.html b/web/index.html index 6c76ee22e..f36299d75 100644 --- a/web/index.html +++ b/web/index.html @@ -18,7 +18,9 @@ in C with more features and better performance.

Latest release

-The latest release is ccache 2.0. This release adds: +The latest release is ccache 2.1. This release fixes a segv introduced +for a a simple compile with 2.0. The 2.0 release had the following +features: