Minecraft server crash every 5 minutes.

Ihave server problem. I'm running craftbukkit 1.5.2, and i have all the time problem "auth of memory". Server works with 20 players 2 monts fine. Now when come 10 crash everytime . I see thah comand /home spend a lot of rams. What can be a problem ?

I have plugins :
essentials,
essentials spawn,
essentials chat,
world guard/edit,
noswear,
nocheatplus,
permissionex, ,
citizens,
simplewarp
chestshop
blacklist


Ihave also that error :
14:48:18
CONSOLE:
[INFO] lestange lost connection: disconnect.quitting
14:48:20
CONSOLE:
[SEVERE] Exception in thread "Connection #22 read thread"
14:48:20
CONSOLE:
[SEVERE] java.lang.OutOfMemoryError: unable to create new native thread
14:48:20
CONSOLE:
[SEVERE] at java.lang.Thread.start0(Native Method)
14:48:20
CONSOLE:
[SEVERE] at java.lang.Thread.start(Unknown Source)
14:48:20
CONSOLE:
[SEVERE] at net.minecraft.server.v1_5_R3.NetworkManager.a(NetworkManager.java:242)
14:48:20
CONSOLE:
[SEVERE] at net.minecraft.server.v1_5_R3.NetworkManager.i(NetworkManager.java:218)
14:48:20
CONSOLE:
[SEVERE] at net.minecraft.server.v1_5_R3.NetworkManager.c(NetworkManager.java:346)
14:48:20
CONSOLE:
[SEVERE] at net.minecraft.server.v1_5_R3.NetworkReaderThread.run(SourceFile:94)

But i dont understoot why crash now ?, and 2 monts before work fine with same version and same plugins. I control server with mcmyadmin. PLeas i spend about 30hours for this problem and still crash.

Before i hve also problem somethink like arrow nay,nay,.. crash but i findout comand /romowe arrows 9999 and disapeart these problem.

Thanks for help.

Matej122

HS_err report :

--------------- T H R E A D ---------------

Current thread (0x00002aafe4169800): JavaThread "C2 CompilerThread1" daemon [_thread_in_native, id=3099, stack(0x00002aaff903f000,0x00002aaff9140000)]

Stack: [0x00002aaff903f000,0x00002aaff9140000], sp=0x00002aaff913b0f0, free space=1008k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x8a03ea] VMError::report_and_die()+0x2ea
V [libjvm.so+0x408f5b] report_vm_out_of_memory(char const*, int, unsigned long, char const*)+0x9b
V [libjvm.so+0x22ac87] Chunk:perator new(unsigned long, unsigned long)+0x107
V [libjvm.so+0x22acff] Arena::grow(unsigned long)+0x3f
V [libjvm.so+0x7b121a] PhaseChaitin::Split(unsigned int)+0x46a
V [libjvm.so+0x346ace] PhaseChaitin::Register_Allocate()+0x48e
V [libjvm.so+0x3b87ed] Compile::Code_Gen()+0x3ad
V [libjvm.so+0x3bb3f5] Compile::Compile(ciEnv*, C2Compiler*, ciMethod*, int, bool, bool)+0xe15
V [libjvm.so+0x32d912] C2Compiler::compile_method(ciEnv*, ciMethod*, int)+0x142
V [libjvm.so+0x3c0313] CompileBroker::invoke_compiler_on_method(CompileTask*)+0x323
V [libjvm.so+0x3c147d] CompileBroker::compiler_thread_loop()+0x43d
V [libjvm.so+0x8602e8] JavaThread::thread_main_inner()+0xc8
V [libjvm.so+0x860438] JavaThread::run()+0x138
V [libjvm.so+0x7420a0] java_start(Thread*)+0x100

EDIT by Moderator: merged posts, please use the edit button instead of double posting.