Sluggish inserts/updates ?

Started by Adam Haberlachalmost 25 years ago2 messages
#1Adam Haberlach
adam@newsnipple.com

I've got a system in which a row is being created by one process,
a notify is sent, and another process finds and then deletes the
row. This whole interchange seems to be taking about a second, which
seems oddly slow. As far as I know, I have the fsync-on-anything
turned off (*).

I'm mainly wondering if I should index/not index the key of the
table, and if I should blame the hardware or Postgres? The hard
drive on the R&D server is pretty slow, although the CPU is pretty
dang fast. I could also blame the notification system but that
shouldn't be a problem, right?

* Is there a good way to find out if this option is on/off?

--
Adam Haberlach |A cat spends her life conflicted between a
adam@newsnipple.com |deep, passionate, and profound desire for
http://www.newsnipple.com |fish and an equally deep, passionate, and
'88 EX500 '00 >^< |profound desire to avoid getting wet.

#2Hannu Krosing
hannu@tm.ee
In reply to: Adam Haberlach (#1)
Re: Sluggish inserts/updates ?

Adam Haberlach wrote:

I've got a system in which a row is being created by one process,
a notify is sent, and another process finds and then deletes the
row. This whole interchange seems to be taking about a second, which
seems oddly slow.

If you do it enough times without vacuum, the table grows quite big,
even
though it may look empty...

As far as I know, I have the fsync-on-anything
turned off (*).

I'm mainly wondering if I should index/not index the key of the
table, and if I should blame the hardware or Postgres?

Index would very likely help. (BTW, the best way to find out is to try
it -
you can always drop it later ;)

The hard
drive on the R&D server is pretty slow, although the CPU is pretty
dang fast. I could also blame the notification system but that
shouldn't be a problem, right?

How do you read the notify ?

----------
Hannu