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Re: what'll make a good mysql server

On 2000-10-13 12:53, t s a d i wrote:
>i actually have 512M of RAM and havent maximized it yet.  is it possible to
>"force" mysql to load all data in RAM just like what you mentioned below?

AFAIK it's not directly possible and probably not desirable.  I think it's 
probably better to have things get cached as they are loaded so that unneeded 
data is not cached.  However something like the following in your mysql start 
scripts will get things in the disk cache quickly:
cat *.db > /dev/null &

>heres my _# free_ output BTW:
>             total       used       free     shared    buffers     cached
>Mem:        517260     318212     199048      13084      15888     244032
>-/+ buffers/cache:      58292     458968
>Swap:       256968          0     256968
>and this is how part of my /etc/mysql/my.cnf looks like BTW just in case you
>guys have some suggestions:
>set-variable = connect_timeout=40
>set-variable = max_connections=300
>set-variable = join_buffer=16M
>set-variable = key_buffer=256M
>set-variable = record_buffer=16M
>set-variable = sort_buffer=16M
>set-variable = max_allowed_packet=2M
>set-variable = thread_stack=128K
>set-variable = table_cache=900

What is the key_buffer?

For best performance you want:
RAM > disk-usage + buffers

So if you actually use 256M of key_buffer (which is probably unlikely in a 
300M database) then you may want 600M of RAM for best performance.

NB  This isn't necessarily the best database optimisation technique.  It's 
just that such amounts of RAM are affordable and it's not overly difficult to 
install it.

>--- Russell Coker <russell@coker.com.au> wrote:
>> On 2000-10-12 19:09, t s a d i wrote:
>> >  what hardware can you recommend?  single processor?  dual?  SCSI's?
>> >  i need all the speed i can get (my mysql db is about 300MB big) ...
>> If you have a small database then the solution to most performance
>> problems is to make RAM larger than the database.  Get 512M of RAM so that
>> after a few minutes all the data is in cache and no data has to be read
>> from disk.
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