Join the community today
Become a Member

Memcached Memcached - before and after graphs!

Discussion in 'Other Centmin Mod Installed software' started by deltahf, Feb 19, 2015.

  1. deltahf

    deltahf Premium Member Premium Member

    360
    170
    43
    Jun 8, 2014
    Ratings:
    +276
    Local Time:
    2:01 AM
    It's not helping much in my high-traffic forum, either. I installed it in the middle of the day (high traffic time), and it didn't do anything but consume a bunch of memcache memory. Here's the NewRelic graphs - the Xen Cache plugin was activated at 5:21:
    Screen Shot 2015-02-25 at 10.38.37 PM 1.png

    Current memcached stats:
    Screen Shot 2015-02-25 at 10.43.19 PM.png



    Perhaps this is why the XenForo developers don't bother caching that data by default, because there's not much benefit to be gained from it? I'm going to disable it now.
     
  2. eva2000

    eva2000 Administrator Staff Member

    44,426
    10,144
    113
    May 24, 2014
    Brisbane, Australia
    Ratings:
    +15,696
    Local Time:
    4:01 PM
    Nginx 1.17.x
    MariaDB 5.5/10.x
    benefit is all relative.. if you have alot of activity/large forum every bit counts as once less hit to database backend :)
     
  3. deltahf

    deltahf Premium Member Premium Member

    360
    170
    43
    Jun 8, 2014
    Ratings:
    +276
    Local Time:
    2:01 AM
    Oh yes, I definitely agree, but in this case I didn't actually see any tangible reduction in database calls.

    Screen Shot 2015-02-25 at 11.11.29 PM.png

    It's also a bit curious that, despite consuming more memory, the cache Request Rate, Hit Rate, Miss Rate, and Set Rate in memcache were virtually the same before and after installing the plugin... Makes me wonder if something wasn't working right?

    Before:
    [​IMG]

    After:
    [​IMG]
     
  4. eva2000

    eva2000 Administrator Staff Member

    44,426
    10,144
    113
    May 24, 2014
    Brisbane, Australia
    Ratings:
    +15,696
    Local Time:
    4:01 PM
    Nginx 1.17.x
    MariaDB 5.5/10.x
    look at items in cache stats ;)

    You also have another layer of cache in the form of browser level caching which would factor in for additional caching offset too.
     
  5. deltahf

    deltahf Premium Member Premium Member

    360
    170
    43
    Jun 8, 2014
    Ratings:
    +276
    Local Time:
    2:01 AM
    True, I suppose it could really help in flash crowd situations, which my site is prone to (traffic can go up 3-4x in one day, and you never know when it's going to happen). I've got plenty of memory, so I suppose I will enable it again.
     
  6. eva2000

    eva2000 Administrator Staff Member

    44,426
    10,144
    113
    May 24, 2014
    Brisbane, Australia
    Ratings:
    +15,696
    Local Time:
    4:01 PM
    Nginx 1.17.x
    MariaDB 5.5/10.x
    All will depend on amount of new first time visitors to your site where they do not have any of your site components cached in their browsers :)
     
  7. Mayank

    Mayank New Member

    7
    2
    3
    Sep 8, 2015
    India
    Ratings:
    +2
    Local Time:
    11:31 AM
    1.9
    10.0.21
    How do I see these graphs on my server? Yesterday I enabled Memcached to be used. I can see memcache details inside my forum software. I am trying to understand if I require any changing in configuration or not. My memory limit is same as it was default installed. But on running stats, I see bytes as so many times more than limit max bytes.
     
  8. eva2000

    eva2000 Administrator Staff Member

    44,426
    10,144
    113
    May 24, 2014
    Brisbane, Australia
    Ratings:
    +15,696
    Local Time:
    4:01 PM
    Nginx 1.17.x
    MariaDB 5.5/10.x
    see Getting Started Guide step 13 Getting Started Guide - CentminMod.com LEMP Nginx web stack for CentOS