Re: MVCC cons - Mailing list pgsql-general

From Ron Johnson
Subject Re: MVCC cons
Date
Msg-id 46C215D3.7000606@cox.net
Whole thread Raw
In response to Re: MVCC cons  (Kenneth Downs <ken@secdat.com>)
Responses Re: MVCC cons
List pgsql-general
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On 08/14/07 14:34, Kenneth Downs wrote:
> Tom Lane wrote:
>> Kenneth Downs <ken@secdat.com> writes:
>>
>>> Speaking as an end-user, I can give only one I've ever seen, which is
>>> performance.  Because of MVCC, Postgres's write performance (insert
>>> and update) appears on my systems to be almost exactly linear to row
>>> size.  Inserting 1000 rows into a table with row size 100 characters
>>> takes twice as long as inserting 1000 rows into a table with row size
>>> 50 characters.
>>>
>>
>> Not sure why you'd think that's specific to MVCC.  It sounds like purely
>> an issue of disk write bandwidth.
>>
>>             regards, tom lane
>>
>
> I did not see this in MS SQL Server.

It is only logical that it will take 2x as long to insert 2x as much
data.

Maybe SQL Server is compressing out white space?  Or (shudder)
heavily caching writes?

- --
Ron Johnson, Jr.
Jefferson LA  USA

Give a man a fish, and he eats for a day.
Hit him with a fish, and he goes away for good!

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