MySQL Bugs: #63989: innodb_buffer_pool_size with 128M default is too large

Bug #63989	innodb_buffer_pool_size with 128M default is too large
Submitted:	11 Jan 2012 8:41	Modified:	11 Jan 2012 8:52
Reporter:	Ryan Chen	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: Options	Severity:	S3 (Non-critical)
Version:	5.5	OS:	Linux
Assigned to:		CPU Architecture:	Any

Description:
The default value has changed from 8M to 128M in 5.5, this default is too large and causing a lot of problem for small MySQL servers, such as server that only can use my-small.cnf

How to repeat:
Run 5.5 on server with 128M Ram and make it busy, it will usually failed to restart with the error:

20111  7:00:12 InnoDB: Initializing buffer pool, size = 128.0M
InnoDB: mmap(137887744 bytes) failed; errno 12
120111  7:00:12 InnoDB: Completed initialization of buffer pool
120111  7:00:12 InnoDB: Fatal error: cannot allocate memory for the buffer pool

Suggested fix:
Changed the default back to 8M, or update the  my-small.cnf to override the value of innodb_buffer_pool_size

"Server with 128M of RAM" sounds like a joke these days, but yes, explicit smaller size setting for innodb_buffer_pool_size in my-small.ini will be useful (for beginners at least).

With things like the Raspberry Pi entering the low end of the "server market" the new default may indeed be a bit high ... not sure how to easily solve this though, maybe have different compile profiles / defaults per target platform?