[CentOS] Performance issues/difference of two servers running same task (one is quicker)

Jobst Schmalenbach
2019-07-06T00:52:06Z

On Thu, Jul 04, 2019 at 10:46:19AM -0700, Gordon Messmer (gordon.messmer at
gmail.com) wrote:
> On 7/3/19 11:43 PM, Jobst Schmalenbach wrote:
> >  - How can it be that the DELL takes so much longer alltough on the
far better hardware?
> It looks like the DIY system has a CPU that's nearly twice as fast
> as the Dell's.? The additional CPU in the Dell will run more tasks
> concurrently, but it won't make a single process faster.
>
> You might also think that the SSD RAID would make the Dell faster,
> but that will only be true if the process that you're testing
> performs a significant amount of IO.? If your DB operations are
> happening mostly in memory (that is, if the data is cached), then
> the faster CPU will be the primary determining factor.

I made the buffer pool size on the DELL double the size of the DIY
when I started trying to figure out why the speed difference.

>
> The other thing that you left out of your description is the amount
> of data on each server.? If your live server has a lot of data in
> its DB and the dev system has a small dataset suitable for testing,
> then generally you'd expect that the dev system's data is more
> likely to live in cache and avoid disk IO, and processing the
> smaller set will also take less CPU time.

Most of the DB's are small as they contain websites.
The biggest DB is the Online Training DB, which are the same on both machine
as I constantly copy the data from the life server to the DIY.



Very good analysis indeed.
Makes total sense.


--
Jobst Schmalenbach
Road to hell is paved with NAND gates.