Error creating new connection: hcommblk.Open: why?

[former_SQLA_member326303]

Whether prompt the cause of the following messages (SQL Anywhere 12.0.1.4178):
Error creating new connection: hcommblk.Open (8) / Shared Memory function newConn failed

I. 07/22 07:25:32. 1: -xs ****
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I. 07/22 07:25:32. 5: -c
I. 07/22 07:25:32. 6: 15%
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I. 07/22 07:25:32. SQL Anywhere Network Server Version 12.0.1.4178
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I. 07/22 07:25:32. Running Windows 7 Build 7601 Service Pack 1 on X86 (X86_64)
I. 07/22 07:25:32. Server built for X86 processor architecture
I. 07/22 07:25:32. 302716K of memory used for caching
I. 07/22 07:25:32. Minimum cache size: 302716K, maximum cache size: 1404940K
I. 07/22 07:25:32. Using a maximum page size of 4096 bytes
I. 07/22 07:25:32. Multiprogramming level: minimum:4, current:20, maximum:80
I. 07/22 07:25:32. Automatic tuning of multiprogramming level is enabled
I. 07/22 07:25:32. TCP using Winsock version 2.2
I. 07/22 07:25:32. IPv6 support enabled
I. 07/22 07:25:32. Database server started at Wed Jul 22 2015 07:25
I. 07/22 07:25:32. Database server will stop at Wed Jul 22 2015 23:45
I. 07/22 07:25:32. Trying to start SharedMemory link ...
I. 07/22 07:25:32.     SharedMemory link started successfully
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I. 07/22 12:52:23. Connection ID 1: disconnecting shared memory client, process id not found
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I. 07/22 12:53:41. Error creating new connection: hcommblk.Open (8)
I. 07/22 12:53:41. Shared Memory function newConn failed
I. 07/22 12:54:17. Error creating new connection: hcommblk.Open (8)
I. 07/22 12:54:17. Shared Memory function newConn failed
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I. 07/22 13:00:01. Database server shutdown requested via server console

[MarkCulp · Accepted solution]

The "hcommblk.Open (8)" message occurs when the server was unable to connect to the client's shared memory block. The "8" is the error code, in this case means ERROR_NOT_ENOUGH_MEMORY. I.e. the server did not have enough memory (address space) to map the shared memory.

You will likely need to either increase the amount of memory on your computer or reduce the max cache size of the server (i.e. use -ch switch to lower the upper bound of the cache).

HTH