iowait - Mailing list pgsql-novice

From Tom Allison
Subject iowait
Date
Msg-id 448A07E1.8090207@tacocat.net
Whole thread Raw
Responses Re: iowait  (Alan Hodgson <ahodgson@simkin.ca>)
List pgsql-novice
I'm not sure if this is typical or not but:

I am running a command:
  COPY email (address,domain) FROM '/tmp/temp.dat';
That is reading in some 1.7 million rows to a table which is defined as:

create table email (
    address varchar(100) primary key,
    domain varchar(100),
    status smallint default 0,
    reason varchar(64),
    last_timestamp timestamp default now(),
    created_timestamp timestamp default now(),
    retry_count smallint default 0
);

I am running it under 'BEGIN' so in theory autocommit is off, which seems to be
the case since there aren't any rows to query.
I've increased the mem_sort to 65535 or 65536.

The whole thing is writing to a partition on a relatively simple EIDE disk.

My iowait is 95-95% according to iostat and it's all pointed at this one disk
partition.  And it's taking a REALLY long time.

Question:
Is this normal for a large data load like this?
Is there something "obvious" I could do in the future to better the situation?
Or am I simply bound by the type of hardware I'm running it on?
Are the number of default values and primary key index going to be the death of me?


pgsql-novice by date:

Previous
From: Adam Witney
Date:
Subject: Re: CREATE ROLE and pg_dump
Next
From: Alan Hodgson
Date:
Subject: Re: iowait