High Memory Usage

Discussion in 'Performance Tweaking' started by WicKd, Jan 7, 2013.

  1. Hello guys,
    Recently, it just caught my attention that my server is having quite a bit of issues with ram usage. For example, being night time, we only have about 80 players online, and it seems we are using 12/24GB of ram. Also, when I installed nolagg to examine some of this issue before, it seemed that our ram was running at +75MB/s (in the red zone). Does anybody happen to know what can be causing it? This is our server specs

    Intel E3-1270v2 Processor
    32GB DDR3 Ram
    64GB SSD

    This is our plugin list:

    The following plugins are custom ones:
    - AutoUpgrader
    - ScavengerWilderness
    - ScavengerBattle
    - ScavengerEnchanting
    Although I dont believe those would be causing the issue.

    If anybody would happen to be able to help me with this issue, it would be great. I am currently using spigot build #371, which is based of the beta build of bukkit. Thank you!

    Best regards,
    #1 WicKd, Jan 7, 2013
    Last edited: Jan 14, 2013
  2. PhanaticD


    try using a dev build they use nibbler arrays which might be less on ram not sure, anyways its not a bad thing to be using half of your ram if you arent seeing lag and such
  3. I just tried installing it and I will post the results in a bit, although instantly, I saw it using already 5GB of ram.
  4. PhanaticD


    maybe you have a lot of entities? post a essentials /gc or worldguard /report
  5. This is my /gc report

    When I just got on the server after I woke up (6 hours from the boot), the server was using 20 GB of ram with only about 80 people. Every time I do /gc, it seems that the free memory decreases
  6. PhanaticD


    that says 20 gigs are free, you are using less than 4..
  7. Yes, but after a few minutes, it seems to drop greatly. Like I said, for example, It was using 8 GB when I went to bed, and when I woke up, it was using 20GB. There was roughly the same amount of people online so I was unsure what was causing it.

    Edit: I started the server minutes before taking this picture
    • Creative Creative x 1
  8. md_5

    Administrator Developer

    You are using ~4gb. Chances are your Xms settings in your startup line are really bad.
  9. Hello, this is my current startup script
    java -Xms24576M -Xmx24576M -jar craftbukkit.jar nogui

    Is there anything in this that you would improve upon? Thank you.

    Best regards,
  10. Why do you have the nogui tag?....
  11. I am currently running on linux.
  12. Would hugepages possibly help this issue with the memory?

    Edit: Ram Usage seems to be at 19GB with only 120 people

    Now its down to 110 people, although ram usage increased even more
    #12 WicKd, Jan 8, 2013
    Last edited: Jan 8, 2013
  13. I have been having lots of memory issues too. 1.4.6 has been horrid for me.

    Do you also get tiny spikes that drop you TPS down a little bit?
  14. Occasionally yes, usually with +225 players
  15. PhanaticD


    what is your view distance? you have a good amount of chunks loaded, if you lower view distance to about 6, players usually wont notice and you will unload a lot of chunks from ram and such
  16. My view distance is only at 4 atm ;(
  17. Are you running into problems getting higher concurrency? What is your server cap, do you hit that, and does your server work when it is at the cap? Having ram used isn't really that big of an issue unless it is spinning out of control and crashing your server. The more things your server hold in memory, the faster it can access them when needed; so having ram used is good, and having ram free is arguably not as good. The screenshots all show 20tps, so I don't think there's a serious concern for the time being...
  18. The server cap is at 300 people, although when the player count gets so high, then the TPS starts dropping. The ram usage at that time would be EXTREMELY low already, sometimes causing the server to be unplayable.
  19. It also seems to drop the TPS greatly after a few hours for an unknown reason, even with low amounts of people.
  20. Unfortunately, im still r.unning into this strange issue. Here are some of the TPS results I have been getting based on time and players.
    300 players, 20min uptime = 6GB ram usage
    200 players, 3 hour uptime = 10GB ram usage
    100 plyers, 10 hour uptime = 16GB ram usage

    I have no idea why this is happening. I have updated my current plugins in the OP. Maybe these timings will help debug?