Hi,

Your database is not big but your settings are low. Change your FB server to 
64bit and increase your dbbuffer or in fbconfig defaultdbcasche setting and use 
superserver. Check your database data page size. I always set it to 16KB. Your 
database utylize memory in this pattern:

Dbpage size * dbbuffers
Or if dbbuffer is 0
Db page size * defaultdbcachepages

You must add to this sort buffer for any connection.

You should also download shnapshot of firebird 2.5.3.xxx to fix windows 2008 
memory problem

Regards,
Karol Bieniasxewski

Wysłane z mojego HTC

----- Reply message -----
Od: "Joshua Hartmann [email protected] [firebird-support]" 
<[email protected]>
Do: <[email protected]>
Temat: [firebird-support] Cache Performance Options
Data: pon., maj 12, 2014 21:32
I am a MSP for a large dental office that uses an application with a Firebird 
DB. I've done a lot of database work in my life, but none with firebird so I 
need a little help with the configurations. The office is complaining of 
slowness and what we've done so far to help them will be below. Keep in mind, I 
am not the developer of the application, just a MSP trying to help them out 
since the developer has no clue what they're doing.

The server is QEMU/KVM virtual server running Microsoft Server 2008 R2. The 
host machine is running Ubuntu Server 12.04.Xeon 12754 cores allocated to the 
virtual server12GB memory allocated to the virtual server (32GB total on the 
host machine)
750GB Momentus Hybrid SSD/HDD's (RAID 0+1 1.5TB total usable)
The database is ~30GB
At first, they were running in classic server mode (FB version 2.1.3 x86) on a 
physical server 2003 machine with 4GB of memory. That machine's HDD's started 
to fail so we just moved it to the new virtual 2008 server.

We let the software company do the install and they set it to classic mode 
(version 2.1.3 x86) but left all options at default. We noticed the server 
would start pretty fast but then throughout the day slow down. When checking 
the system's resources, I noticed it was maxing out on RAM and moving to the 
page file which explained the slowness. However, task manager did not display 
that memory was actually being used by the fbserver.exe processes.

I asked the developer to switch it to superserver because I read its better for 
shared cache and since all the clients are accessing the same data (appointment 
lists, patient lists, etc) I thought it would speed things up. It didn't change 
the memory usage and fbserver.exe still only reported using about 60MB.

So I started reading through articles online and found a bunch of optimization 
and cache settings. I changed the database options for async, set page buffers 
at 60k, and turned off auto sweeping. I also changed the firebird.conf 
settings. Specifically, the MaxFileSystemCache. None of it made any difference.

Next, I upgraded to 2.5.2 (still x86) and its made a little difference. I still 
notice the fbserver using quite a bit of disk IO though and its still not very 
fast.
I guess my questions are:
In my situation, should I be using all file system cache or firebird cache? 
Essentially, what should I set my page buffers and FileSystemCacheThreshole to? 
I've already set my FileSystemCache to 90%.Should I enable or disable async?
Should I enable auto sweeping or not?Would performance be faster if we upgraded 
to the 64bit version of 2.5.2?
Thanks for any advice you can give.
-Josh







Reply via email to