Horrible Lag In Singleplayer But Not In Multiplayer

Please force a crash by pressing F3 + C for 10 seconds while in-game and attach the crash report ([minecraft/crash-reports/crash-<DATE>-client.txt|http://hopper.minecraft.net/help/finding-minecraft-data-folder]) here.

Please attach the complete output of the "Game Output (Your Minecraft name) " which can be found on the fourth tab of the launcher.

If the launcher closes after game start, please edit your profile and select "Launcher visibility" then, "Keep the launcher open".

Alright here it is:

Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.

Time: 6/24/15 6:27 AM
Description: Manually triggered debug crash

java.lang.Throwable
at ave.s(SourceFile:1587)
at ave.av(SourceFile:888)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)

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

– Head –
Stacktrace:
at bdb.a(SourceFile:309)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bew['Mkezar'/1877, l='MpServer', x=-17.01, y=64.00, z=507.96]]
Chunk stats: MultiplayerChunkCache: 3110, 3110
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: -8.00,64.00,256.00 - World: (-8,64,256), Chunk: (at 8,4,0 in -1,16; contains blocks -16,0,256 to -1,255,271), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 694 game time, 694 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
Forced entities: 86 total; [we['Zombie'/2611, l='MpServer', x=-84.03, y=30.00, z=470.63], vn['Creeper'/2612, l='MpServer', x=-86.50, y=32.00, z=478.50], uz['item.item.seeds'/2625, l='MpServer', x=-78.09, y=63.00, z=487.22], uz['item.item.seeds'/2626, l='MpServer', x=-77.41, y=63.00, z=488.34], to['Cow'/2627, l='MpServer', x=-79.50, y=63.00, z=512.50], to['Cow'/2629, l='MpServer', x=-65.50, y=70.00, z=585.50], to['Cow'/2630, l='MpServer', x=-67.50, y=71.00, z=585.50], to['Cow'/2631, l='MpServer', x=-66.50, y=70.00, z=587.50], vn['Creeper'/2642, l='MpServer', x=-55.72, y=29.00, z=474.16], vn['Creeper'/2643, l='MpServer', x=-56.41, y=29.00, z=476.69], vn['Creeper'/2644, l='MpServer', x=-51.94, y=29.00, z=477.38], vn['Creeper'/2645, l='MpServer', x=-60.53, y=28.00, z=478.59], tk['Bat'/2646, l='MpServer', x=-56.28, y=28.00, z=488.56], vn['Creeper'/2647, l='MpServer', x=-58.50, y=36.00, z=489.50], vn['Creeper'/2648, l='MpServer', x=-57.50, y=36.00, z=488.50], wa['Skeleton'/2649, l='MpServer', x=-57.50, y=36.00, z=490.50], vn['Creeper'/2650, l='MpServer', x=-55.66, y=37.00, z=485.06], we['Zombie'/2651, l='MpServer', x=-58.03, y=11.00, z=553.41], we['Zombie'/2652, l='MpServer', x=-52.56, y=19.00, z=552.56], tx['Squid'/101, l='MpServer', x=-70.09, y=60.50, z=446.38], tx['Squid'/102, l='MpServer', x=-74.69, y=62.38, z=448.03], tx['Squid'/103, l='MpServer', x=-68.50, y=61.59, z=454.03], tx['Squid'/104, l='MpServer', x=-71.31, y=61.88, z=458.22], wa['Skeleton'/2665, l='MpServer', x=-47.88, y=14.00, z=522.75], tx['Squid'/105, l='MpServer', x=-69.97, y=61.72, z=456.91], tk['Bat'/2666, l='MpServer', x=-43.63, y=38.97, z=575.38], tk['Bat'/2667, l='MpServer', x=-39.78, y=33.94, z=587.06], we['Zombie'/2668, l='MpServer', x=-40.50, y=23.00, z=578.50], we['Zombie'/2669, l='MpServer', x=-27.94, y=32.00, z=579.59], we['Zombie'/2670, l='MpServer', x=-45.72, y=31.00, z=580.31], vn['Creeper'/2681, l='MpServer', x=-23.50, y=31.00, z=579.50], to['Cow'/2709, l='MpServer', x=-2.75, y=64.00, z=581.31], to['Cow'/2710, l='MpServer', x=-3.97, y=64.00, z=585.97], to['Cow'/158, l='MpServer', x=-22.50, y=67.00, z=434.50], to['Cow'/159, l='MpServer', x=-22.50, y=67.00, z=434.50], to['Cow'/160, l='MpServer', x=-22.50, y=67.00, z=436.50], to['Cow'/161, l='MpServer', x=-22.50, y=67.00, z=434.50], tk['Bat'/169, l='MpServer', x=-5.34, y=17.09, z=465.97], wa['Skeleton'/2739, l='MpServer', x=7.50, y=12.00, z=506.09], to['Cow'/2740, l='MpServer', x=4.28, y=64.00, z=513.75], to['Cow'/2741, l='MpServer', x=13.50, y=67.00, z=500.28], to['Cow'/2742, l='MpServer', x=-5.47, y=64.00, z=583.69], to['Cow'/2743, l='MpServer', x=5.50, y=64.00, z=578.50], tk['Bat'/209, l='MpServer', x=8.94, y=18.16, z=454.81], to['Cow'/2772, l='MpServer', x=16.50, y=67.00, z=504.50], to['Cow'/2773, l='MpServer', x=24.16, y=68.00, z=515.91], tk['Bat'/2774, l='MpServer', x=41.78, y=19.56, z=530.66], we['Zombie'/2795, l='MpServer', x=46.50, y=25.00, z=501.50], to['Cow'/2796, l='MpServer', x=53.81, y=64.00, z=507.53], to['Cow'/2797, l='MpServer', x=41.06, y=66.00, z=496.94], to['Cow'/2798, l='MpServer', x=42.88, y=66.00, z=500.47], to['Cow'/2799, l='MpServer', x=44.81, y=66.00, z=501.81], tk['Bat'/2800, l='MpServer', x=47.53, y=26.13, z=513.78], to['Cow'/2801, l='MpServer', x=35.19, y=67.00, z=524.78], to['Cow'/2802, l='MpServer', x=36.53, y=67.00, z=523.16], to['Cow'/2803, l='MpServer', x=40.97, y=68.00, z=515.97], to['Cow'/2804, l='MpServer', x=40.94, y=68.00, z=520.00], tv['Sheep'/2826, l='MpServer', x=56.50, y=64.00, z=478.34], tv['Sheep'/2827, l='MpServer', x=53.00, y=64.00, z=478.25], tk['Bat'/2829, l='MpServer', x=55.50, y=15.97, z=492.56], we['Zombie'/2830, l='MpServer', x=58.50, y=29.00, z=490.50], we['Zombie'/2831, l='MpServer', x=57.56, y=29.00, z=490.56], we['Zombie'/2832, l='MpServer', x=53.31, y=29.00, z=494.25], vn['Creeper'/2833, l='MpServer', x=54.50, y=30.00, z=484.50], vn['Creeper'/2834, l='MpServer', x=56.22, y=30.00, z=483.59], vn['Creeper'/2835, l='MpServer', x=52.94, y=30.00, z=472.59], tv['Sheep'/2837, l='MpServer', x=51.06, y=64.00, z=481.13], tv['Sheep'/2838, l='MpServer', x=45.22, y=64.00, z=483.53], tk['Bat'/2839, l='MpServer', x=60.84, y=14.56, z=497.47], we['Zombie'/2840, l='MpServer', x=51.72, y=25.00, z=503.22], we['Zombie'/2841, l='MpServer', x=53.66, y=25.00, z=502.41], we['Zombie'/2842, l='MpServer', x=58.72, y=22.00, z=506.50], wa['Skeleton'/2843, l='MpServer', x=56.50, y=57.00, z=536.50], to['Cow'/2844, l='MpServer', x=51.59, y=65.00, z=570.78], to['Cow'/2845, l='MpServer', x=52.81, y=65.00, z=569.16], to['Cow'/2846, l='MpServer', x=53.50, y=72.00, z=573.50], to['Cow'/2847, l='MpServer', x=50.00, y=65.00, z=570.50], to['Cow'/2848, l='MpServer', x=55.84, y=64.00, z=566.03], to['Cow'/2849, l='MpServer', x=60.53, y=65.00, z=573.53], to['Cow'/2850, l='MpServer', x=52.13, y=66.00, z=573.03], to['Cow'/2851, l='MpServer', x=60.53, y=65.00, z=573.53], tk['Bat'/2859, l='MpServer', x=57.16, y=14.88, z=493.47], bew['Mkezar'/1877, l='MpServer', x=-17.01, y=64.00, z=507.96], tk['Bat'/4597, l='MpServer', x=45.38, y=23.00, z=495.09], tk['Bat'/4598, l='MpServer', x=46.47, y=25.03, z=501.25], tk['Bat'/4599, l='MpServer', x=45.84, y=24.66, z=496.53]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at bdb.a(SourceFile:309)
at ave.b(SourceFile:2293)
at ave.a(SourceFile:334)
at net.minecraft.client.main.Main.main(SourceFile:124)

– System Details –
Details:
Minecraft Version: 1.8.7
Operating System: Windows 7 (amd64) version 6.1
CPU: 2x AMD Phenom(tm) II X2 550 Processor
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 153645112 bytes (146 MB) / 1060372480 bytes (1011 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 1.8.7
LWJGL: 2.9.4
OpenGL: GeForce GTX 660/PCIe/SSE2 GL version 4.5.0 NVIDIA 347.88, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)

Memory: 153645112 bytes (146 MB) / 1060372480 bytes (1011 MB) up to 1060372480 bytes (1011 MB)

You're running out of Memory. Assign more RAM to Minecraft, see MC-12949.

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