Oh, and what's up with the thread_concurrency being 6? That doesn't
make any sense unless you have a tri-processor setup.
> -----Original Message-----
> From: Ledet, Mike [mailto:MLedet@stripped]
> Sent: Wednesday, December 04, 2002 11:01 AM
> To: 'mysql@stripped'
> Subject: Slow performance using 3.23 on RH 8.0
>
>
> I'm running Mysql 3.23.52 on a Redhat 8.0 installation
> booting to Gnome.
> The machine is a dual AMD 1800, 1 gig of ram, one Ultra ATA
> IDE drive, and 2
> 18 gig scsi 10,000 RPM drives on a RAID controller running Raid 0.
>
> I've got everything except /db on the IDE drive, /db is the
> only thing on
> the raid array.
>
> I've got a couple of smallish tables and one larger table
> with about 7 gigs
> of data. The larger table is a fixed row format table with
> each row being
> 462 bytes wide. I have a primary auto increment int column
> and a unique
> index on a varchar 60. Pack keys is off, delayed key writes on.
>
> With this kind of hardware I was expecting pretty good
> performance, but I
> haven't seen it yet. I finally decided something was wrong
> when I had to
> run an alter table on the 7 gig table, adding 3 columns, a
> varchar 12, a
> varchar 50, and a datetime columm.... and it took over 10
> HOURS to complete.
>
> That seems way too slow to me...
>
> I've included relevant portions (the uncommented portions)
> from my.cnf, the
> OS installation was fairly vanilla, using defaults for just about
> everything. The file system is ext3.
>
> Any suggestions or things I haven't included that you need?
> Sorry if I'm
> doing something really stupid here... relatively new to Linux
> after a lot of
> years of windoze.
>
> Thanks in advance
>
> Mike
>
> ********** my.cnf *************
>
> [mysqld]
> port = 3306
> socket = /var/lib/mysql/mysql.sock
> datadir = /db/mysql
> skip-locking
> set-variable = key_buffer=500M
> set-variable = max_allowed_packet=2M
> set-variable = table_cache=512
> set-variable = sort_buffer=22M
> set-variable = record_buffer=22M
> set-variable = thread_cache=8
> # Try number of CPU's*2 for thread_concurrency
> set-variable = thread_concurrency=6
> set-variable = myisam_sort_buffer_size=64M
> log-bin
> server-id = 0
> tmpdir = /tmp/
> [mysqldump]
> quick
> set-variable = max_allowed_packet=16M
>
> [mysql]
> no-auto-rehash
> # Remove the next comment character if you are not familiar with SQL
> #safe-updates
>
> [isamchk]
> set-variable = key_buffer=500M
> set-variable = sort_buffer=8M
> set-variable = read_buffer=10M
> set-variable = write_buffer=30M
>
> [myisamchk]
> set-variable = key_buffer=500M
> set-variable = sort_buffer=8M
> set-variable = read_buffer=10M
> set-variable = write_buffer=30M
> [mysqlhotcopy]
> interactive-timeout
>
>
>
