Skip to main content

Apache is not using available ram

lorio
Any idea where to look when apache 2.2 prefork is not using RAM. 8GB or 16GB available. 8GB and 16GB and only 900MB RAM are used. Centos 6 x64 Apache 2.2 Prefork + SuPHP. Even when putting a lot of connection on php applications. Looks like a bottleneck somewhere else.

Comments

7 comments

Date Votes
  • Skamasle
    Maybe apache not need more ? If there is no errors on error_log, apache not need more memory... Or maybe you have setup apache limits under "Apache Configuration"
    0
  • lorio
    Thanks for your response. The limit is set to: RLimitMEM 1462711978 Error.log apache shows nothing relevant. Business as usual. Might be the case that Apache in combination with SuPHP and MySQL is not the bottleneck. Higher load but no change in RAM above 9XX MB of 16XXX MB is a bit strange. Swapspace is not used at all. Running on a VPS 16 GB RAM 8 CPU Cores under SSD RAID In that situation Apache is showing already "..reading.. " on the status screen. I am overlooking something simple. Just a sar output to get a picture about the system resource usage. 03:10:01 PM all 2.01 0.01 0.74 0.00 0.01 97.23 03:20:01 PM all 17.44 0.01 4.84 0.03 0.05 77.62 03:30:02 PM all 39.58 0.00 11.65 0.05 0.09 48.62 03:40:01 PM all 56.44 0.01 16.95 0.05 0.11 26.44 03:50:01 PM all 38.84 0.01 11.99 0.08 0.10 49.00 04:00:01 PM all 36.27 0.01 11.33 0.07 0.09 52.23 04:10:01 PM all 48.09 0.01 14.92 0.07 0.12 36.80 04:20:01 PM all 44.62 0.00 14.04 0.08 0.11 41.15 04:30:01 PM all 44.96 0.01 14.41 0.09 0.11 40.43 04:30:01 PM CPU %user %nice %system %iowait %steal %idle 04:40:02 PM all 58.92 0.01 18.60 0.05 0.12 22.29 04:50:01 PM all 57.58 0.01 18.54 0.08 0.12 23.67 05:00:01 PM all 58.41 0.01 18.50 0.06 0.15 22.86 05:10:01 PM all 45.81 0.01 14.74 0.09 0.12 39.24 05:20:01 PM all 44.53 0.01 14.13 0.09 0.11 41.13 05:30:01 PM all 40.15 0.01 13.03 0.10 0.10 46.61 05:40:01 PM all 39.36 0.00 12.47 0.09 0.11 47.96 05:50:01 PM all 38.47 0.01 12.10 0.09 0.11 49.22 06:00:01 PM all 37.98 0.01 12.15 0.11 0.10 49.66 06:10:01 PM all 36.83 0.01 11.67 0.09 0.10 51.30 06:20:01 PM all 36.73 0.01 11.42 0.10 0.10 51.64 06:30:01 PM all 36.07 0.01 11.20 0.09 0.10 52.54 06:40:01 PM all 29.27 0.01 9.11 0.08 0.08 61.45 06:50:01 PM all 32.16 0.01 9.96 0.09 0.09 57.70 07:00:01 PM all 32.77 0.01 10.47 0.09 0.09 56.57 07:10:01 PM all 29.19 0.01 9.28 0.08 0.08 61.36 07:20:01 PM all 32.13 0.00 10.08 0.09 0.09 57.60 07:30:02 PM all 33.68 0.00 10.65 0.09 0.09 55.48 07:40:01 PM all 35.62 0.01 11.39 0.08 0.10 52.80 07:50:02 PM all 32.15 0.01 10.22 0.09 0.09 57.44 08:00:01 PM all 35.03 0.01 11.27 0.09 0.10 53.51 08:10:02 PM all 30.13 0.00 9.72 0.09 0.09 59.96 08:20:01 PM all 24.41 0.00 7.74 0.08 0.07 67.69 08:30:01 PM all 25.10 0.01 8.06 0.07 0.07 66.68 08:40:01 PM all 29.43 0.01 9.28 0.07 0.09 61.13 08:50:01 PM all 27.04 0.00 8.42 0.07 0.08 64.39 09:00:01 PM all 26.19 0.01 8.34 0.08 0.08 65.31 09:10:01 PM all 21.41 0.01 6.94 0.07 0.07 71.51 09:20:01 PM all 20.16 0.01 6.49 0.07 0.06 73.21
    Beside the ..reading.. apache status I haven't found a real issue. suPHP is always a CPU hog. I wonder what is possible when sticking to suPHP in combination to prefork.
    0
  • cPanelMichael
    Hello :) To clarify, are you experiencing any actual slowness or reduced performance, or are you simply concerned that RAM is not utilized? Thank you.
    0
  • lorio
    ]Hello :) To clarify, are you experiencing any actual slowness or reduced performance, or are you simply concerned that RAM is not utilized?

    There where a few problems in terms of performance. I used the time to pinpoint the issues. From time to time I just get tricked by the different top tools like atop and htop, htop uses a different memory display method. So RAM is used when taking a look at top as a comparism. Mem: 16442108k total, 9337636k used, 7104472k free, 493572k buffers Swap: 1048572k total, 0k used, 1048572k free, 8112172k cached The main issue on the VPS seems to be suPHP and it's demand for CPU power. I wonder what hardware is needed to allow e.g. 100 concurrent connections to a php script (e.g. forum) under suPHP. DSO seems to be no option in terms of security. Is there a heavy traffic (in terms of concurrent users) site which still sticks to suPHP? I cannot believe it.
    0
  • cPanelMichael
    ]DSO seems to be no option in terms of security.

    Have you looked into using DSO with Mod_Ruid2? Apache Module: ModRuid2 Thread: Mod_ruid2 vs suPHP: costs vs benefits Thank you.
    0
  • lorio
    ]Have you looked into using DSO with Mod_Ruid2? Thread: Mod_ruid2 vs suPHP: costs vs benefits

    I already posted in that thread. Still not convinced about the php handlers. Are mod-ruid2 and suphp still actively developed? FastCGI and FPM (FastCGI Process Manager) might be the way to go.
    0
  • cPanelMichael
    There are no plans to remove support for Mod_Ruid2. You can find a thread on the EOL for suPHP at: suPHP EOL However, there's potential for a replacement that's under development by Cloud Linux:
    0

Please sign in to leave a comment.

Didn't find what you were looking for?

New post