I described a problem earlier this month that has been plaguing
the site ( http://librepathology.org
) I am running.
The short version is:
- I am using the InstantCommons feature of MediaWiki.
- Intermittently, the images on the site are disappearing.
- Unusual about it is that the images pages that are created when
MediaWiki pulls an image from the WikiCommons seem to disappear too.
- It resolves shortly after I reboot the server.
- It has happened a couple of times in the past few weeks... but not
- It does not have a clear relation to server load, i.e. the
images do not disappear only when the loading is high.
- It has been my observation that free (physical) memory
(shown using the unix command 'top') is still available but low
when problems are happening. I do have a swap partition
What I have done:
- Upgraded RAM to 2 GB (from 1 GB)
- Removed backup files from the server -- so I have ~15% free space.
- Tried to block a high bandwidth robot with robots.txt
- Looked through log files... no sure where to look though.
- I have taken down a citation generator that I installed
a few weeks before this all started.
I think the problem lies in the memory management.
The "memory_limit" variable in "php.ini" (/etc/php5/apache2/php.ini)
I do have caching enabled in LocalSettings.php
( $wgMainCacheType = CACHE_ACCEL; ) but not otherwise.
I ran the site similarly configured over a year behind
a login... without anything like this happening.
At the bottom is output from 'cat /proc/meminfo' taken
at time the images were broken.
Any thoughts/suggestions would be appreciated.
MemTotal: 2012148 kB
MemFree: 89368 kB
Buffers: 230104 kB
Cached: 1098764 kB
SwapCached: 120 kB
Active: 900608 kB
Inactive: 779988 kB
Active(anon): 256448 kB
Inactive(anon): 128280 kB
Active(file): 644160 kB
Inactive(file): 651708 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 1113084 kB
SwapFree: 1111164 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 351628 kB
Mapped: 54936 kB
Shmem: 33000 kB
Slab: 218796 kB
SReclaimable: 208732 kB
SUnreclaim: 10064 kB
KernelStack: 792 kB
PageTables: 8144 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 2119156 kB
Committed_AS: 783648 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9140 kB
VmallocChunk: 34359728411 kB
HardwareCorrupted: 0 kB
AnonHugePages: 0 kB
Hugepagesize: 2048 kB
DirectMap4k: 40948 kB
DirectMap2M: 2007040 kB