Question Regarding symm optimizer

The "right" number of DRV devices depends upon a few factors ...

1) size of devices you want to optimize (in your case, 8.4 and 33.4 Gb)
2) number of swaps you want to perform at the same time (let's suppose 4 swaps)

In your environment I'd create 4x 8.4 DRV and 4x 33.4 DRV devices.
Optimizer won't care about protection (the same 8.4 DRV device will be good for both a 8.4 RAID5 and an 8.4 mirror device).

It's better to create DRV devices on fast devices. This will give the smallest possible migration time. Since it looks like your drives are all the same, you can forget about that

Are you using metavolumes ??

If we need to make 4 swaps...do we need to have 8 DRVs?...as I was thinking we need 2 DRVs for each swap...also, on what type of devices do we create DRVs (are DRVs created on Raid 5 devs etc)? also what should be the drive sizes from which we will be creating DRVs..

Also If I have 300gb drives along with 146gb then I need to create DRVs only on 146gb drives and can I create DRVs on both drives...

Yes I am also using meta volumes...do I need to consider any other things???

Thanks for the reply....

DRV devices must match size of devices you want to swap. But they won't care about protection. If you have 8.4 RAID5 devices and 8.4 mirrored devices, you need only 8.4 DRV devices. Oh BTW DRV devices are unprotected, but don't be scared since the code will "add" a DRV to your existing device while moving slices in the backend thus your data is always protected

If you have metadevices, considere you are going to optimize single members, not the whole meta. Thus if your 33.4 lun is made out of 4 smaller (8.4gb) devices, you don't need 33.4 gb DRV devices.

You need 2 DRV for every swap .. that's why I suggested you to create 4x 8.4gb and 4x 33.4gb DRV devices (thus creating 8 DRV devices and allowing up to 4 swaps at the same time).

If you have different drives in the backend. considere placing DRV devices on fast drives .. However you don't need different DRV in different disk groups.

Can we make 8 swaps at a time...what is the maximum number of swaps we can make?

Also, If I have a 5x33.4gb meta and If I want to optimize the whole meta...Then what size of DRVs I should create? Also, for what type of other devices we can create DRVs and for what type of devices is symopt is not suppoted?

Thank u....:)

UR welcome