Re: Question about LWLockAcquire's use of semaphores instead

Luis Alberto Amigo Navarro <lamigo@atc.unican.es>

View thread View on postgr.es

From: "Luis Alberto Amigo Navarro" <lamigo@atc.unican.es>

To: "Bruce Momjian" <pgman@candle.pha.pa.us>, <bruc@acm.org>

Cc: "Tom Lane" <tgl@sss.pgh.pa.us>, <pgsql-hackers@postgresql.org>

Date: 2002-07-30T15:23:53Z

Lists: pgsql-hackers

Attachments

Imagen1.png (image/png)

----- Original Message -----
From: "Bruce Momjian" <pgman@candle.pha.pa.us>
To: <bruc@acm.org>
Cc: "Tom Lane" <tgl@sss.pgh.pa.us>; <pgsql-hackers@postgresql.org>
>
> We would have to understand how the SGI code is better than our existing
> code on SMP machines.
>

I've been searching for data from SGI's Origin presentation to illustrate
what am I saying, this graph only covers Memory bandwith, but take present
that as distance between nodes increase, memory access latency is also
increased: