I've been playing on my server in the snapshot completely vanilla. Every around 10-60 minutes the server crashes and I get a report. Here is the report:

---- Minecraft Crash Report ----
// This is a token for 1 free hug. Redeem at your nearest Mojangsta: _HUG~

Time: 8/1/14 6:38 PM
Description: Watching Server

java.lang.Error
at java.lang.Thread.sleep(Native Method)
at pk.a(SourceFile:265)
at net.minecraft.server.MinecraftServer.run(SourceFile:475)
at java.lang.Thread.run(Unknown Source)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at java.lang.Thread.sleep(Native Method)
at pk.a(SourceFile:265)

– Thread Dump –
Details:
Threads: "Keep-Alive-Timer" Id=129 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at sun.net.www.http.KeepAliveCache.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

"pool-3-thread-29" Id=116 TIMED_WAITING on java.util.concurrent.SynchronousQueue$TransferStack@18d11e5f
at sun.misc.Unsafe.park(Native Method)

• waiting on java.util.concurrent.SynchronousQueue$TransferStack@18d11e5f
  at java.util.concurrent.locks.LockSupport.parkNanos(Unknown Source)
  at java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(Unknown Source)
  at java.util.concurrent.SynchronousQueue$TransferStack.transfer(Unknown Source)
  at java.util.concurrent.SynchronousQueue.poll(Unknown Source)
  at java.util.concurrent.ThreadPoolExecutor.getTask(Unknown Source)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
  ...

"Netty Server IO #15" Id=34 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@146cca47
• locked java.util.Collections$UnmodifiableSet@6a484b69
• locked sun.nio.ch.EPollSelectorImpl@16e5b315
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #14" Id=33 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@1f6161ba
• locked java.util.Collections$UnmodifiableSet@706dd593
• locked sun.nio.ch.EPollSelectorImpl@175437c
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #13" Id=32 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@1a87b8e4
• locked java.util.Collections$UnmodifiableSet@bbe14e1
• locked sun.nio.ch.EPollSelectorImpl@244e0ba0
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #12" Id=31 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@18a1b647
• locked java.util.Collections$UnmodifiableSet@26201f54
• locked sun.nio.ch.EPollSelectorImpl@20925941
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #11" Id=30 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@29d8f06
• locked java.util.Collections$UnmodifiableSet@18171326
• locked sun.nio.ch.EPollSelectorImpl@4cfed6d6
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #10" Id=29 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@399973d4
• locked java.util.Collections$UnmodifiableSet@187fa822
• locked sun.nio.ch.EPollSelectorImpl@2be9f1bb
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #9" Id=28 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@2019ac9b
• locked java.util.Collections$UnmodifiableSet@7118b33
• locked sun.nio.ch.EPollSelectorImpl@2e9d9eff
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #8" Id=27 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@77b42ceb
• locked java.util.Collections$UnmodifiableSet@4efc6532
• locked sun.nio.ch.EPollSelectorImpl@4cb85710
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #7" Id=26 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@4ebb0877
• locked java.util.Collections$UnmodifiableSet@bd31409
• locked sun.nio.ch.EPollSelectorImpl@45541351
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #6" Id=25 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@f5b1428
• locked java.util.Collections$UnmodifiableSet@72c41f84
• locked sun.nio.ch.EPollSelectorImpl@21362bf2
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #5" Id=24 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@6a9e8e2c
• locked java.util.Collections$UnmodifiableSet@7248135f
• locked sun.nio.ch.EPollSelectorImpl@1ab009fb
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #4" Id=23 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@d50ef25
• locked java.util.Collections$UnmodifiableSet@1a0deb2b
• locked sun.nio.ch.EPollSelectorImpl@77c17a24
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #3" Id=22 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@7ca8c1c5
• locked java.util.Collections$UnmodifiableSet@71d8c838
• locked sun.nio.ch.EPollSelectorImpl@383ad09a
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #2" Id=21 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@4ac2bb46
• locked java.util.Collections$UnmodifiableSet@7619a04c
• locked sun.nio.ch.EPollSelectorImpl@4b81fccf
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Netty Server IO #1" Id=20 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@579e8490
• locked java.util.Collections$UnmodifiableSet@4229e180
• locked sun.nio.ch.EPollSelectorImpl@5038422c
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"File IO Thread" Id=39 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at bqr.c(SourceFile:51)
at bqr.run(SourceFile:30)
at java.lang.Thread.run(Unknown Source)

"Server Watchdog" Id=37 RUNNABLE
at sun.management.ThreadImpl.dumpThreads0(Native Method)
at sun.management.ThreadImpl.dumpAllThreads(Unknown Source)
at pp.run(SourceFile:39)
at java.lang.Thread.run(Unknown Source)

"Netty Server IO #0" Id=19 RUNNABLE (in native)
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(Unknown Source)
at sun.nio.ch.EPollSelectorImpl.doSelect(Unknown Source)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(Unknown Source)

• locked io.netty.channel.nio.SelectedSelectionKeySet@5f498eb0
• locked java.util.Collections$UnmodifiableSet@323be061
• locked sun.nio.ch.EPollSelectorImpl@2e5c49a
  at sun.nio.ch.SelectorImpl.select(Unknown Source)
  at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:618)
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:306)
  at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
  ...

"Server console handler" Id=16 RUNNABLE (in native)
at java.io.FileInputStream.readBytes(Native Method)
at java.io.FileInputStream.read(Unknown Source)
at java.io.BufferedInputStream.read1(Unknown Source)
at java.io.BufferedInputStream.read(Unknown Source)

• locked java.io.BufferedInputStream@3ace5bf2
  at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
  at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
  at sun.nio.cs.StreamDecoder.read(Unknown Source)
• locked java.io.InputStreamReader@21219a66
  at java.io.InputStreamReader.read(Unknown Source)
  ...

"DestroyJavaVM" Id=15 RUNNABLE

"Server thread" Id=13 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at pk.a(SourceFile:265)
at net.minecraft.server.MinecraftServer.run(SourceFile:475)
at java.lang.Thread.run(Unknown Source)

"Server Infinisleeper" Id=12 TIMED_WAITING
at java.lang.Thread.sleep(Native Method)
at pl.run(SourceFile:64)

"Snooper Timer" Id=11 TIMED_WAITING on java.util.TaskQueue@251faf88
at java.lang.Object.wait(Native Method)

• waiting on java.util.TaskQueue@251faf88
  at java.util.TimerThread.mainLoop(Unknown Source)
  at java.util.TimerThread.run(Unknown Source)

"Signal Dispatcher" Id=5 RUNNABLE

"Finalizer" Id=3 WAITING on java.lang.ref.ReferenceQueue$Lock@433d1cc2
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.ReferenceQueue$Lock@433d1cc2
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.ReferenceQueue.remove(Unknown Source)
  at java.lang.ref.Finalizer$FinalizerThread.run(Unknown Source)

"Reference Handler" Id=2 WAITING on java.lang.ref.Reference$Lock@612b270a
at java.lang.Object.wait(Native Method)

• waiting on java.lang.ref.Reference$Lock@612b270a
  at java.lang.Object.wait(Object.java:503)
  at java.lang.ref.Reference$ReferenceHandler.run(Unknown Source)

Stacktrace:
at pp.run(SourceFile:55)
at java.lang.Thread.run(Unknown Source)

– System Details –
Details:
Minecraft Version: 14w31a
Operating System: Linux (amd64) version 2.6.18-371.8.1.el5
Java Version: 1.7.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1345940912 bytes (1283 MB) / 2077753344 bytes (1981 MB) up to 2077753344 bytes (1981 MB)
JVM Flags: 10 total; -Xms2048M -Xmx2048M -XX:MaxPermSize=128M -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+UseAdaptiveGCBoundary -XX:-UseGCOverheadLimit -XX:+DisableExplicitGC -XX:ErrorFile=/dev/null -XX:UseSSE=3
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Profiler Position: N/A (disabled)
Player Count: 3 / 20; [qr['SharkDice'/3846643, l='world', x=406.42, y=87.00, z=94.44], qr['BrutustheOrc'/4072349, l='world', x=250.10, y=73.69, z=-3.50], qr['Radridinghood'/4099133, l='world', x=335.56, y=66.00, z=26.96]]
Is Modded: Unknown (can't tell)
Type: Dedicated Server (map_server.txt)