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[EP-tech] Re: Eprints Server Freezes Often

Hi,

Its been almost 24 hours since I made the changes in the apache config
file. What I have noticed after the changes is that the number of httpd
processes is averaging less than 30. Before making the changes in config
file, I have noticed that at times the number of httpd processes would be
130+. That's when the server would freeze.

So, the changes in the config file is keeping the number of httpd process
under control. However, just a while ago, I noticed that the eprints
server was taking a long time to respond. I checked the number of httpd
processes, there were 22 of them and the 'top' command produced the
following output:

top - 17:03:33 up 5 days,  5:17,  1 user,  load average: 2.94, 3.55, 2.80
Tasks: 167 total,   2 running, 165 sleeping,   0 stopped,   0 zombie
Cpu(s): 25.6%us,  0.6%sy,  0.0%ni, 49.2%id, 24.6%wa,  0.0%hi,  0.0%si,
0.0%st
Mem:   4051536k total,  4025724k used,    25812k free,     5304k buffers
Swap:  8193108k total,  4098224k used,  4094884k free,    66116k cached

There is clear indication that the  free memory is quite low. I restarted
the httpd server and the output of the 'top' command right after the
restart is:

top - 17:05:57 up 5 days,  5:19,  1 user,  load average: 12.27, 6.11, 3.78
Tasks: 160 total,   1 running, 159 sleeping,   0 stopped,   0 zombie
Cpu(s):  2.2%us,  0.2%sy,  0.0%ni, 92.8%id,  4.8%wa,  0.0%hi,  0.0%si,
0.0%st
Mem:   4051536k total,   335168k used,  3716368k free,     7644k buffers
Swap:  8193108k total,   263748k used,  7929360k free,    69500k cached

More than 3.5GB of main memory has been freed after the httpd restart. Is
there anything else that needs to be done to maintain the optimal memory
level to ensure that the eprints server response level is consistent?

Thanks for your attention, Francis
Your server is using a lot of swap (4GB) so this will definitely slow things down a lot.
Check the memory size of a single apache process, and limit the max number of processes so that apache doesn't take over your entire memory (leave some for mysql and other services..).
As for your mysql connections, EPrints should use one mysql connection per process so make sure mysql has more connections available than there are apache processes running. 

Seb.