Cliff, ----- Original Message ----- From: ""Cliff"" <[EMAIL PROTECTED]> Newsgroups: mailing.database.myodbc Sent: Saturday, March 13, 2004 11:32 PM Subject: Re: InnoDB tables using 90% cpu
> Well I recompiled with Linuxthreads with the same result. I ran explain on > both queries and the only difference is innodb looks at 31 rows where myisam > looked at 23. Both are of type range. Is there anything else I can do before > giving up on innodb? how much slower is the query with InnoDB? What are the absolute times for MyISAM and InnoDB? Can you post the query and the EXPLAIN? Since the CPU usage is 90 %, it is clearly CPU-bound. And CPU-bound queries should run in about the same time for InnoDB and MyISAM, if the EXPLAIN is the same. Also post the output of SHOW INNODB STATUS. Best regards, Heikki Tuuri Innobase Oy Foreign keys, transactions, and row level locking for MySQL InnoDB Hot Backup - a hot backup tool for InnoDB which also backs up MyISAM tables http://www.innodb.com/order.php Register now for the 2004 MySQL Users Conference! http://www.mysql.com/events/uc2004/index.html > ----- Original Message ----- > From: "Chris Nolan" <[EMAIL PROTECTED]> > To: "Sasha Pachev" <[EMAIL PROTECTED]> > Cc: "Cliff" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> > Sent: Tuesday, March 09, 2004 7:14 PM > Subject: Re: InnoDB tables using 90% cpu > > > > Sasha Pachev wrote: > > > > > Cliff wrote: > > > > > >> The query is running dramatically slower than the MyISAM query, > > >> sometimes > > >> even causing mysql to freeze for a while. I searched this list and > > >> found a > > >> few people saying that on FreeBSD mysql should be compiled using linux > > >> pthreads if you are using InnoDB or else I would get this exact > > >> problem. Has > > >> this been resolved or is should I recompile? I am using native freebsd > > >> threads. > > > > > > > > > Compare the output of EXPLAIN for both MyISAM and InnoDB. Also, if you > > > have a Linux or even Windows system around, test the same query on > > > them to see if there is any difference. > > > > > > I am not that familiar with FreeBSD, but from what I've seen, I would > > > tend to use the approach "when in doubt, use LinuxThreads". The advice > > > you've got does make sense - InnoDB runs a number of background > > > threads, so if your thread implementation is lacking, it would hurt > > > InnoDB more than MyISAM. > > > > > FreeBSD's thread library is a user-space setup. This can result in major > > performance issues when doing things that block. > > > > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
