Re: LWLock cache line alignment - Mailing list pgsql-hackers

From Neil Conway
Subject Re: LWLock cache line alignment
Date
Msg-id 42023868.9030601@samurai.com
Whole thread Raw
In response to LWLock cache line alignment  ("Simon Riggs" <simon@2ndquadrant.com>)
List pgsql-hackers
Simon Riggs wrote:
> ...and BTW, what is MMCacheLock?? is that an attempt at padding already?

One would hope not, as it would be a totally braindead attempt :) It 
appears to have been formerly used by smgr/mm.c; when that was removed, 
the MMCacheLock should have been removed but was not. Barring any 
objections, I'll remove it from HEAD tomorrow.

> It looks like padding out LWLock struct would ensure that each of those
> were in separate cache lines?

Sounds like it might be worth trying; since it would be trivial to 
implement for testing purposes, I'd be curious to see if this improves 
performance, and/or has any effect on the CS storm issue.

-Neil


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