From: mark@mark.mielke.cc
To: Anthony Presley <anthony@resolution.com>
To: pgsql-performance@postgresql.org
Subject: Re: 64-bit vs 32-bit performance ... backwards?
Date: Mon, 12 Jun 2006 22:16:27 -0400
Message-ID: <20060613021627.GA4682@mark.mielke.cc> (raw)
In-Reply-To: <20060613000441.GI8588@kenobi.snowman.net>
References: <1150151282.14661.42.camel@tigger>
<20060613000441.GI8588@kenobi.snowman.net>
I've been trying to track this stuff - in fact, I'll likely be
switching from AMD32 to AMD64 in the next few weeks.
I believe I have a handle on the + vs - of 64-bit. It makes sense that
full 64-bit would be slower. At an extreme it halfs the amount of
available memory or doubles the required memory bandwidth, depending
on the work load.
Has anybody taken a look at PostgreSQL to ensure that it uses 32-bit
integers instead of 64-bit integers where only 32-bit is necessary?
32-bit offsets instead of 64-bit pointers? This sort of thing?
I haven't. I'm meaning to take a look. Within registers, 64-bit should
be equal speed to 32-bit. Outside the registers, it would make sense
to only deal with the lower 32-bits where 32-bits is all that is
required.
Cheers,
mark
--
mark@mielke.cc / markm@ncf.ca / markm@nortel.com __________________________
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To: pgsql-performance@postgresql.org
Cc: mark@mark.mielke.cc, anthony@resolution.com
Subject: Re: 64-bit vs 32-bit performance ... backwards?
In-Reply-To: <20060613021627.GA4682@mark.mielke.cc>
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