Filip, Of course, there often no easy answer. One thing that I would
mention, the IBM Lab Services team has a team that will come and help you
learn the tools and help you with evaluating your performance issues.
These workshop are reasonably affordable, and often can be covered
at least partially with Power System vouchers if you have any.
If you are interested or need a contact, please reach out to me directly.
Thanks. Tim Rowe - timmr@xxxxxxxxxx
Tim Rowe, timmr@xxxxxxxxxx
Business Architect Application Development & Systems Management for IBM i
IBM i Development Lab, Rochester, MN
(507) 253-6191 (Tie) 553-6191
message: 5
date: Thu, 28 Feb 2019 13:54:36 +0000
from: Filip Drzewiecki via MIDRANGE-L <midrange-l@xxxxxxxxxxxxxxxxxx>
subject: Performance issues after moving more into SQL
Hello,
I observe more and more performance issues with our application and they
started to show up after we've introduced a lot of SQL to our system.
We've did a lot of optimization but even after that we still have some
problems and I'm trying to understand what tools I can use to see if hard
drives are out bottleneck or maybe it is CPU.
System setup (from program/database perspective) is quite complicated.
We've moved from DDS to SQL tables(most tables) and MQT (materialized
query tables, biggest tables ) but programs were not changed and most of
them still use native I/O (but we have SQL behind because of RPG Open
Access and MQT/Indexes). I understand that we may have some overhead
because of this(on CPU) but for example MQT Updates/Insert are quite slow
but we use the for Read operation because chain operation with sql behind
was very slow without MQT. Of course we use SQL triggers in this setup.
We do not have EasyTier license and from what I've read it could tell us
if we could benefit from SSD. I've also found something about SSD Analyzer
([1]
http://www-01.ibm.com/support/docview.wss?uid=tss1prs3780) but only
for 7.1 and it look like it does not work on 7.3 (I could not see it as
collection in iNavigator
We have machine type 8286-41A (power8) with 3 LPARS which has few HDD
drives (raid 5) and StorWize 5010 with few HDD Drives. Unfortunately we do
not have VIOS and LPAR 1 (master) expose HDD to DEV LPAR and PROD LPAR.
This of course should and will be changed but to be honest I have no idea
how much performance we may get if we start use VIOS.
Now I'm totally lost which tools/commands could tell me if response time
from our HDD is weak point and this is why we have slow read/write times
and our CPU does nothing because it waits for HDD(and we should buy few
SSD for hot files). We have Performance Tool so I can use collections
services/performance monitor and then print one of available reports but
there are so many of them. I guess disk report can be used.
Do You have any advices what should I check here?
Filip
References
Visible links
1.
http://www-01.ibm.com/support/docview.wss?uid=tss1prs3780
midrange.com
