[MC-76376] Memory Leak and Tick speed

This spams the console with only one player on the server. While standing at spawn I do not seem to have this spam the console, but as I venture further out through the map this starts to spam the console (Slight variant each time). This is in debug mode, but I am assuming this causes the lag spikes (Warning cannot keep up with server error)

Here is a link to what seems to be others with the exact same issue

http://www.minecraftforum.net/forums/support/server-support/2205991-1-8-server-crashing-skipping-ticks

[Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded?

[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk.recheckGaps' took aprox 100.977362 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk' took aprox 106.730703 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks' took aprox 112.091694 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 118.255128 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 118.608247 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 118.967678 ms
[06:37:18] [Server thread/WARN]: Something's taking too long! 'root' took aprox 119.504795 ms
[06:37:25] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner' took aprox 422.627479 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk.recheckGaps' took aprox 101.630706 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk' took aprox 117.091154 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk.recheckGaps' took aprox 109.624471 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk' took aprox 111.382491 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk.recheckGaps' took aprox 101.790449 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks.tickChunk' took aprox 103.417843 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.tickBlocks' took aprox 433.979968 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 864.156385 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 864.606252 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 864.983491 ms
[06:37:26] [Server thread/WARN]: Something's taking too long! 'root' took aprox 865.373127 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner' took aprox 141.52976 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 158.067112 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 158.633533 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 158.985849 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root' took aprox 159.337368 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 102.116817 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 102.741317 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 103.067681 ms
[06:37:44] [Server thread/WARN]: Something's taking too long! 'root' took aprox 103.558964 ms
[06:37:59] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner' took aprox 316.884846 ms
[06:37:59] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 329.813771 ms
[06:37:59] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 330.224033 ms
[06:37:59] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 330.474154 ms
[06:37:59] [Server thread/WARN]: Something's taking too long! 'root' took aprox 330.856069 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner.recheckGaps' took aprox 105.1787 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner.recheckGaps' took aprox 108.504752 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner' took aprox 247.54337 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 255.724714 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 256.029966 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 256.259085 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root' took aprox 256.69035 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick.mobSpawner' took aprox 303.470289 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world.tick' took aprox 313.382704 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels.world' took aprox 313.836947 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root.levels' took aprox 314.218438 ms
[06:38:28] [Server thread/WARN]: Something's taking too long! 'root' took aprox 314.940271 ms

Less Important/Unimportant

I have tried multiple different flags, no flags, adjusting memory, etc..... What is suggested? just -server?

java -server -Xmx3596M -Xms3596M -jar server.jar nogui

java -server -Xmx3596M -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+DisableExplicitGC -XX:+AggressiveOpts -jar server.jar nogui

java -Xms4092 -Xmx4092 -XX:+UseParallelOldGC -server -jar server.jar nogui

I also have used the suggested script at http://minecraft.gamepedia.com/Tutorials/Server_startup_script which looks something like (with the variable adjusted multiple times of course...):

java -Xmx${MAXHEAP}M -Xms${MINHEAP}M -XX:+UseConcMarkSweepGC \
 -XX:+CMSIncrementalPacing -XX:ParallelGCThreads=$CPU_COUNT -XX:+AggressiveOpts \
 -jar $SERVICE $OPTIONS

I have used multiple suggested JVM flags but with little or no change. (Most of them made the server less stable) I also have adjusted the Memory heap by lowering it just to make sure there is some overhead for other applications running (However I do have 500MB of swap just in case, though I am like99% sure that probably is a bad idea, I have since turned it off and on but do not think that the server every has needed to use it or attempted to, though I am not a professional!)

I thought perhaps it is the size of the map that may be causing this, but I would assume this shouldn't be the case... (I have no done testing on a server with a limited boarder other than the default)

I have also been told that building above the nether may cause the lag, but have not spent time in MCEdit looking to see if anyone has done so.

Comments

kumasasa 2015-01-10T09:36:50Z

What specs (CPU, RAM) has the computer ?

migrated 2015-01-11T04:19:17Z

I was running on a 8GB 6Core with 250Up and 1GB Down and this persisted. I will put together in-depth details ASAP.

(And running on my home computers had the same effect with no one on.)

kumasasa 2015-01-12T07:17:51Z

What's the server start script ?

migrated 2015-01-12T23:45:30Z

I have tried to update the information to the best of my ability

migrated 2015-01-14T11:34:22Z

Awaiting a response, thank you..

kumasasa 2015-01-14T19:39:08Z

C'mon...

migrated 2015-01-14T20:11:55Z

I do not know what that is suppose to mean? It this a bug or just due to the system not truly being able to handle it?

migrated 2015-01-15T04:23:15Z

Another computer tested on and receiving the same issue... "Can't keep up!"

processor : 0vendor_id : GenuineIntelcpu family : 6model : 45model name : Intel(R) Xeon(R) CPU @ 2.60GHzstepping : 7microcode : 0x1cpu MHz : 2600.000cache size : 20480 KBphysical id : 0siblings : 2core id : 0cpu cores : 1apicid : 0initial apicid : 0fpu : yesfpu_exception : yescpuid level : 13wp : yesflags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc nopl xtopology eagerfpu pni pclmulqdq ssse3 cx16 sse4_1 sse4_2 x2apic popcnt aes xsave avx hypervisor lahf_lm xsaveoptbogomips : 5200.00clflush size : 64cache_alignment : 64address sizes : 46 bits physical, 48 bits virtualpower management:processor : 1vendor_id : GenuineIntelcpu family : 6model : 45model name : Intel(R) Xeon(R) CPU @ 2.60GHzstepping : 7microcode : 0x1cpu MHz : 2600.000cache size : 20480 KBphysical id : 0siblings : 2core id : 0cpu cores : 1apicid : 1initial apicid : 1fpu : yesfpu_exception : yescpuid level : 13wp : yesflags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc nopl xtopology eagerfpu pni pclmulqdq ssse3 cx16 sse4_1 sse4_2 x2apic popcnt aes xsave avx hypervisor lahf_lm xsaveoptbogomips : 5200.00clflush size : 64cache_alignment : 64address sizes : 46 bits physical, 48 bits virtualpower management:

MemTotal: 13338112 kBMemFree: 6464048 kBMemAvailable: 10171852 kBBuffers: 688 kBCached: 3815620 kBSwapCached: 0 kBActive: 6023924 kBInactive: 433788 kBActive(anon): 2641640 kBInactive(anon): 8304 kBActive(file): 3382284 kBInactive(file): 425484 kBUnevictable: 0 kBMlocked: 0 kBSwapTotal: 0 kBSwapFree: 0 kBDirty: 3104 kBWriteback: 0 kBAnonPages: 2641436 kBMapped: 43788 kBShmem: 8484 kBSlab: 167796 kBSReclaimable: 137956 kBSUnreclaim: 29840 kBKernelStack: 1120 kBPageTables: 12032 kBNFS_Unstable: 0 kBBounce: 0 kBWritebackTmp: 0 kBCommitLimit: 6669056 kBCommitted_AS: 9053020 kBVmallocTotal: 34359738367 kBVmallocUsed: 30740 kBVmallocChunk: 34359697880 kBHardwareCorrupted: 0 kBAnonHugePages: 2428928 kBHugePages_Total: 0HugePages_Free: 0HugePages_Rsvd: 0HugePages_Surp: 0Hugepagesize: 2048 kBDirectMap4k: 57336 kBDirectMap2M: 3088384 kBDirectMap1G: 12582912 kB

migrated 2015-01-19T01:53:07Z

The tick averages at 3000ms off and happens ever 45seconds (persistent) Ill see if I can narrow down the problem...

kumasasa 2015-11-16T22:16:44Z

Is this still an issue in the current Minecraft Snapshot 15w46a or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

migrated 2015-11-30T17:36:09Z

I wont be able to test this thoroughly until January (As I assume my old worlds are beyond corruption) I will launch a new server soon and let you know if I receive the same results.

migrated 2017-02-14T14:59:46Z

Ticket resolved as incomplete, because no answer in a reasonable amount of time (1+ year), if it still happens, please update the ticket.