Search Postgresql Archives

INSERT - UPDATE throughput oscillating and SSD activity after stopping the client

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,
I've two tables, t1 and t2, both with one bigint id indexed field and one 256 char data field; t1 has always got 10000 row, while t2 is increasing as explained in the following.

My pqlib client countinously updates  one row in t1 (every time targeting a different row) and inserts a new row in t2. All this in blocks of 1000 update-insert per commit, in order to get better performance.
Wal_method is fsync, fsync is on, attached my conf file. 
I've a 3.8ghz laptop with evo SSD.

Performance is  measured every two executed blocks and related to these blocks.

Over the first few minutes performance is around 10Krow/s then it slowly drops, over next few minutes to 4Krow/s, then it slowly returns high and so on, like a wave.
I don't understand this behaviour. Is it normal? What does it depend on?

Also, when I stop the client I see the SSD light still heavily working. It would last quite a while unless I stop the postgresql server, in this case it suddenly stops. If I restart the server it remains off.
I'm wondering if it's normal. I'd like to be sure that my data are safe once commited.

Regards
Pupillo

P.S.: I put this question in general questions as my concern is not if the performance is high or not.









Attachment: postgresql.conf
Description: Binary data

-- 
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux