Re: Joel's Performance Issues WAS : Opteron vs Xeon - Mailing list pgsql-performance

From Joel Fradkin
Subject Re: Joel's Performance Issues WAS : Opteron vs Xeon
Date
Msg-id 001701c5480e$57e7fad0$797ba8c0@jfradkin
Whole thread Raw
In response to Re: Joel's Performance Issues WAS : Opteron vs Xeon  ("Jim C. Nasby" <decibel@decibel.org>)
Responses Re: Joel's Performance Issues WAS : Opteron vs Xeon
List pgsql-performance
I would very, very strongly encourage you to run multi-user tests before
deciding on mysql. Mysql is nowhere near as capable when it comes to
concurrent operations as PostgreSQL is. From what others have said, it
doesn't take many concurrent operations for it to just fall over. I
can't speak from experience because I avoid mysql like the plague,
though. :)

I am just testing the water so to speak, if it cant handle single user tests
then multiple user tests are kind of a waste of time.

I am trying to de-normalize my view into a table to see if I can get my app
to work. It is a good idea anyway but raises a ton of questions about
dealing with the data post a case being closed etc; also on multiple child
relationships like merchandise and payments etc.

I did do a test of all three (MSSQL, MYSQL,and postgres) in aqua studio ,
all on the same machine running the servers and found postgres beat out
MYSQL, but like any other test it may have been an issue with aqua studio
and mysql in any case I have not made a decision to use mysql I am still
researching fixes for postgres.

I am waiting to here back from Josh on using cursors and trying to flatten
long running views.

I am a little disappointed I have not understood enough to get my analyzer
to use the proper plan, we had to set seqscan off to get the select from
response_line to work fast and I had to turn off merge joins to get assoc
list to work fast. Once I am up I can try to learn more about it, I am so
glad there are so many folks here willing to take time to educate us newb's.



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