Have I pushed the limits of my current VPS or is there room for optimization?
- by JRameau
I am currently on a mediatemple DV server (basic) 512mb dedicated ram, this is a CentOS based VPS with Plesk and Virtuozzo. My experience with it from day 1 has been bad and I only could sooth my server issues with several caching "Band-aids," but my sites are not as small as they were a year ago either so the issues have worsen.
I have 3 Drupal installs running on separate (plesk) domains, 1 of those drupal installs is a multisite, that consists of 5-6 sites 2 of those sites are bringing in actual traffic. Those caching "Band-aids" I mentioned are APC, which seemed to help alot initially, and Drupal's Boost, which is considered a poorman's Varnish, it makes all my pages static for anonymous users.
Last 30day combined estimate on Google Ananlytics: 90k visitors 260k pageviews.
Issue: alot of downtime, I am continually checking if my sites are up, and lately I have been finding it down more than 3 times daily. Restarting Apache will bring it back up, for some time. I have google search every error message and looked up ways to optimize my DV server, and I am beyond stump what is my next move. Is this server bad, have I hit a impossibly low restriction such as the 12mb kernel memory barrier (kmemsize), is it on my end, do I need to optimize some more?
*I have provided as much information as I can below, any help or suggestions given will be appreciated
Common Error messages I see in the log:
[error] (12)Cannot allocate memory: fork: Unable to fork new process
[error] make_obcallback: could not import mod_python.apache.\n
Traceback (most recent call last):
File "/usr/lib/python2.4/site-packages/mod_python/apache.py", line 21, in ?
import traceback
File "/usr/lib/python2.4/traceback.py", line 3, in ?
import linecache
ImportError: No module named linecache
[error] python_handler: no interpreter callback found.
[warn-phpd] mmap cache can't open /var/www/vhosts/***/httpdocs/*** - Too many open files in system (pid ***)
[alert] Child 8125 returned a Fatal error... Apache is exiting!
[emerg] (43)Identifier removed: couldn't grab the accept mutex
[emerg] (22)Invalid argument: couldn't release the accept mutex
cat /proc/user_beancounters:
Version: 2.5
uid resource held maxheld barrier limit failcnt
41548: kmemsize 4582652 5306699 12288832 13517715 21105036
lockedpages 0 0 600 600 0
privvmpages 38151 42676 229036 249036 0
shmpages 16274 16274 17237 17237 2
dummy 0 0 0 0 0
numproc 43 46 300 300 0
physpages 27260 29528 0 2147483647 0
vmguarpages 0 0 131072 2147483647 0
oomguarpages 27270 29538 131072 2147483647 0
numtcpsock 21 29 300 300 0
numflock 8 8 480 528 0
numpty 1 1 30 30 0
numsiginfo 0 1 1024 1024 0
tcpsndbuf 648440 675272 2867477 4096277 1711499
tcprcvbuf 301620 359716 2867477 4096277 0
othersockbuf 4472 4472 1433738 2662538 0
dgramrcvbuf 0 0 1433738 1433738 0
numothersock 12 12 300 300 0
dcachesize 0 0 2684271 2764800 0
numfile 3447 3496 6300 6300 3872
dummy 0 0 0 0 0
dummy 0 0 0 0 0
dummy 0 0 0 0 0
numiptent 14 14 200 200 0
TOP: (In January the load avg was really high 3-10, I was able to bring it down where it is currently is by giving APC more memory play around with)
top - 16:46:07 up 2:13, 1 user, load average: 0.34, 0.20, 0.20
Tasks: 40 total, 2 running, 37 sleeping, 0 stopped, 1 zombie
Cpu(s): 0.3% us, 0.1% sy, 0.0% ni, 99.7% id, 0.0% wa, 0.0% hi, 0.0% si
Mem: 916144k total, 156668k used, 759476k free, 0k buffers
Swap: 0k total, 0k used, 0k free, 0k cached
MySQLTuner: (after optimizing every table and repairing any table with overage I got the fragmented count down to 86)
[--] Data in MyISAM tables: 285M (Tables: 1105)
[!!] Total fragmented tables: 86
[--] Up for: 2h 44m 38s (409K q [41.421 qps], 6K conn, TX: 1B, RX: 174M)
[--] Reads / Writes: 79% / 21%
[--] Total buffers: 58.0M global + 2.7M per thread (100 max threads)
[!!] Query cache prunes per day: 675307
[!!] Temporary tables created on disk: 35% (7K on disk / 20K total)
