DO vs AO vs System tuner...

[jasontch]

anyone who know the difference between system tunner and AO.... as i Know...

DO : is a software the we can tune VV to other RAID level or drive type to get better servicel level optimization..

AO: is a sub-volume tiering software that we can move hot chunklet to other storage tier by policy and this an be managed via system reporter software..

System Tuner software: this sofware can identifies and relocates underperforming chunklets to optimize performance and eliminate bottlenecks, does this mean system tuner also can move chunket to better servicel level or drive or virtual volume? who has experice with system tuner? and how is it differnce compare to AO? How to run it? From IMC or system reporter? or ????

Appreciate if anyone who know system tuner, please share with us, thanks-

[Richard Siemers]

You pretty much nailed it in your post.

AO: Sub-volume tiering, can move hotter chunk lets to a higher tier, and also move colder chunk lets to a slower tier. I don't have it, but my understanding is this software allows a VV to live across multiple CPGs based on performance policies.. hot chunks go to this CPG, cold chunks to that one...

DO: Moves an entire VV from one CPG to another. This allows raid levels and drive types are defined at the CPG level. I think these types of moves are focused on redistributing chunk lets based on capacity, relaying the VV out evenly across all the available spindles.

System Tuner: This does tuning at the physical disk level based on performance, trying to swap hot and cold chunk lets around within the same spindle type to balance out workload. Command for this is tunepd. I don't own this one either, was talked out of it every time I asked about it. "you should never need it due to the nature of wide striping and they rarely sell it."

Sorry I couldn't help more... I am curious about it... might be work a 90 day free trial.

[sid]

Don't have system tuner but have DO. DO comes with tunesys (-dr for dry run) which checks for imbalances in logical disk usage across nodes amoungst other things. It then runs re-layouts on the ld's to balance them out. Takes a while but works and helps when you add new pd's.

If you do have concerns with the service times on your pd's then system reporter can compare up to 16 pd's with the highest service times (or groups of 16 named pd's). Looking at all 100+ disks in our array there's no sign of any real 'hot' disks.

AO is only really needed if you have multiple disk types. If you have a mix of SSD and NL then probably a must have to make use of the features you have discussed.

[Richard Siemers]

If you do have concerns with the service times on your pd's then system reporter can compare up to 16 pd's with the highest service times (or groups of 16 named pd's). Looking at all 100+ disks in our array there's no sign of any real 'hot' disks.

While it is not possible to have more than 16 colors, it is possible to get more than
16 lines in a graph with the colors being re-used. You can do this by adding the parameter
maxgraphs=<max lines> to the web query. For example to re-run a report with up to 32 lines add this to the end of url: &maxgraphs=32

Also, if you're having timeout issues with system reporter because of these monster queries we're now able to run, you can edit the apache "Timeout" value. On windows the config file is located C:\Program Files\Apache Software Foundation\Apache2.2\conf\httpddefault.conf

[Richard Siemers]

Don't have system tuner but have DO. DO comes with tunesys (-dr for dry run) which checks for imbalances in logical disk usage across nodes amoungst other things. It then runs re-layouts on the ld's to balance them out. Takes a while but works and helps when you add new pd's.

tunesys is a new 3.1.1 command, I am planning a upgrade from 2.3.1 mainly to "Eval" this feature to rebalance across some newly added capacity. I have DO, just not Tuner and according to the 3.1.1 cli doc its part of system tuner. Can you confirm tunesys works without system tuner licensed?

Thanks!

--Richard

[sid]

Yes, on 3.1.1 and can use tunesys without the system tuner license, see below

License features currently enabled:
Dynamic Optimization
InForm Suite
System Reporter
Thin Conversion
Thin Copy Reclamation
Thin Persistence
Thin Provisioning
Virtual Copy

[Richard Siemers]

Thank you very much!

[Perconte]

How often would you say is usefull to run tunesys?