Tuning the Squid Package¶
Some users have reported that adding the following Loader Tunable has greatly increased performance:
See Hardware Tuning and Troubleshooting for more information on that setting.
Some people have also seen better performance by using the ufs cache
filesystem setting. When using ufs filesystem,
vfs.read_max=32 may be
vfs.read_max=128 in System > Advanced, Sytem Tunables
Squid keeps a cache index journal called
swap.state in the top level of the
squid cache folder, typically
/var/squid/cache/swap.sate. This file can
grow very large and consume all hard drive space. To ensure this does not
happen, set a Log Rotate value in the squid configuration.
By setting a number of days to retain the logs, the squid package will activate a nightly cron job which runs:
squid -k rotate
Part of this rotation process includes compacting the
keeping it from getting too large.
If this file is too large and needs to be removed, this may be done while squid is running. After the file is removed, run:
squid -k rotate
This will cause it to be written out again (but compacted). Alternately, tell squid to perform a clean shutdown with:
squid -k shutdown
This will also write the
swap.state file out again, but squid will
stop after this and must be restarted, so it is a less desirable option.
swap.state file is removed while squid is not running, it will have
to completely rescan the cache folder to rebuild it once squid restarts. This
can be a lengthy and time consuming process. It may be better to remove the
contents of the existing cache folder, and rebuild the structure again by
See the Squid FAQ entry for more details.
There could be any number of reasons not to do the following things. Be careful, and test any changes.
Caching Windows Updates¶
These settings could break things, but when it works it works beautifully!
If there are a bunch of local PCs that need Windows Updates, but a WSUS server is not an option, squid can cache them.
On the General Settings tab of the squid configuration (Services > Proxy Server), place the following patterns recommended by Squid in the Custom Options box at the bottom:
refresh_pattern -i windowsupdate.com/.*\.(cab|exe|ms[i|u|f|p]|[ap]sf|wm[v|a]|dat|zip|psf) 43200 80% 129600 reload-into-ims refresh_pattern -i microsoft.com/.*\.(cab|exe|ms[i|u|f|p]|[ap]sf|wm[v|a]|dat|zip|psf) 43200 80% 129600 reload-into-ims refresh_pattern -i windows.com/.*\.(cab|exe|ms[i|u|f|p]|[ap]sf|wm[v|a]|dat|zip|psf) 43200 80% 129600 reload-into-ims refresh_pattern -i microsoft.com.akadns.net/.*\.(cab|exe|ms[i|u|f|p]|[ap]sf|wm[v|a]|dat|zip|psf) 43200 80% 129600 reload-into-ims refresh_pattern -i deploy.akamaitechnologies.com/.*\.(cab|exe|ms[i|u|f|p]|[ap]sf|wm[v|a]|dat|zip|psf) 43200 80% 129600 reload-into-ims range_offset_limit none
On the Cache Management tab of the Squid configuration:
Change Hard Disk Cache size to something large, say
4000(3GB or 4GB), to accommodate the updates.
Change the Maximum object size to something big, such as
512000for 512MB. Going bigger may be needed if any updates larger than that size are released.
Caching Mac Updates¶
refresh_pattern ([^.]+.|)(download|adcdownload).(apple.|)com/.*\.(pkg|dmg) 4320 100% 43200 reload-into-ims
Caching AVG and other Updates¶
As above, but add this before the other options. The same warnings apply:
refresh_pattern ([^.]+.|)avg.com/.*\.(bin) 4320 100% 43200 reload-into-ims refresh_pattern ([^.]+.|)spywareblaster.net/.*\.(dtb) 4320 100% 64800 reload-into-ims refresh_pattern ([^.]+.|)symantecliveupdate.com/.*\.(zip|exe) 43200 100% 43200 reload-into-ims refresh_pattern ([^.]+.|)avast.com/.*\.(vpu|vpaa) 4320 100% 43200 reload-into-ims
Tweaking Update Caching / Squid seems to download on its own¶
As an alternative, also try:
quick_abort_min 0 KB quick_abort_max 0 KB
To ensure that a file is only downloaded if a user actually receives 70% or more of it. Otherwise if a user requests a file and then aborts, it will download the whole file.
range_offset_limit is set to
-1 the quick abort options will NOT
Setting parent proxy available at the Proxy server: Upstream proxy settings tab. In most cases, these settings work if the parent proxy also squid.
To use a parent proxy on another server (not squid), it is necessary to disable Upstream proxy settings, and use the Custom options in the Proxy server: General settings tab.