svn commit: r280323 - head/sys/kern

[Dmitry Morozovsky]

On Sat, 21 Mar 2015, Konstantin Belousov wrote:

> > >   Somewhat modernize the SysV shm code:
> > 
> > Interesting.
> > 
> > Is my understanding correct that postgres still uses shm?  If so,
> > has someone benchmarked the speedup?
> 
> Yes, some versions of Postgres still use SysV shm.  

To be clarified: IIUC, *all* contemporary versions of PostgreSQL do use SHM for 
shatrd buffers (as PgSQL use process-per-connection model)

> But note that the code changed only works during shared segment creation and 
> teardown. Page faults are handled by the same VM code as it was before.
>
> In other words, I expect that nothing changes WRT benchmarks.

On the other hand, I also do not see anything that could change benchmarks 
significally


-- 
Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
[ FreeBSD committer:                                 marck at FreeBSD.org ]
------------------------------------------------------------------------
*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
------------------------------------------------------------------------