Server Crash

[Jealleo]

My server keeps crashing seemingly at random. It can go for days without
crashing and then sometimes it crashes within an hour.

I had not seen anything strange until finally today. 
This was what I saw:

1007: 'script_model', origin: 0.000000 0.000000 0.000000
1008: 'script_model', origin: -1752.983032 28.341913 613.990967
1009: 'script_model', origin: 0.000000 0.000000 0.000000
1010: 'script_model', origin: 0.000000 0.000000 0.000000
1011: 'script_model', origin: 0.000000 0.000000 0.000000
1012: 'script_model', origin: 0.000000 0.000000 0.000000
1013: 'script_model', origin: 2896.659424 34.542171 610.565796
1014: 'script_model', origin: 0.000000 0.000000 0.000000
1015: 'script_model', origin: 0.000000 0.000000 0.000000
1016: 'script_model', origin: 0.000000 0.000000 0.000000
1017: 'script_model', origin: 0.000000 0.000000 0.000000
1018: 'script_model', origin: 0.000000 0.000000 0.000000
1019: 'script_model', origin: 0.000000 0.000000 0.000000
1020: 'tempEntity', origin: -110.000000 -4496.000000 -42.000000
1021: 'tempEntity', origin: 2048.000000 3392.000000 376.000000
********************
ERROR: G_Spawn: no free entities
********************
----- Server Shutdown -----
Sending heartbeat to coduomaster.activision.com
==== ShutdownGame ====
---------------------------
Hunk_Clear: reset the hunk ok 

What is the problem and how do I fix it?

Target

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