From: Stephan Szabo <sszabo@megazone.bigpanda.com>
To: Luke Lonergan <LLonergan@greenplum.com>
Cc: dlang@invendra.net
Cc: pgsql-performance@postgresql.org
Subject: Re: Hardware/OS recommendations for large databases (
Date: Sun, 27 Nov 2005 07:48:01 -0800 (PST)
Message-ID: <20051127072933.Q62040@megazone.bigpanda.com> (raw)
In-Reply-To: <3E37B936B592014B978C4415F90D662DE11EBC@MI8NYCMAIL06.Mi8.com>
References: <3E37B936B592014B978C4415F90D662DE11EBC@MI8NYCMAIL06.Mi8.com>
On Sun, 27 Nov 2005, Luke Lonergan wrote:
> Has anyone done the math.on the original post? 5TB takes how long to
> scan once? If you want to wait less than a couple of days just for a
> seq scan, you'd better be in the multi-gb per second range.
Err, I get about 31 megabytes/second to do 5TB in 170,000 seconds. I think
perhaps you were exaggerating a bit or adding additional overhead not
obvious from the above. ;)
---
At 1 gigabyte per second, 1 terrabyte should take about 1000 seconds
(between 16 and 17 minutes). The impressive 3.2 gigabytes per second
listed before (if it actually scans consistently at that rate), puts it at
a little over 5 minutes I believe for 1, so about 26 for 5 terrabytes.
The 200 megabyte per second number puts it about 7 hours for 5
terrabytes AFAICS.
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: sszabo@megazone.bigpanda.com, LLonergan@greenplum.com, dlang@invendra.net
Subject: Re: Hardware/OS recommendations for large databases (
In-Reply-To: <20051127072933.Q62040@megazone.bigpanda.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox