Expander questions for expander newbie

[lunadesign]

I have a few LSI 9260/9270 cards but have never used any of them with an expander (ie, Intel RES2SV240). I was wondering...

1) If I fully populate all 8 ports on an 9270-8i with drives and then add an expander and move some of the drives from the onboard ports to the expander ports, is the move transparent? Or will I have to tweak things in WebBIOS or in the OS (VMware ESXi)?

2) Is there any performance degradation when a drive (more specifically, a high performance SSD) is connected to the expander instead of directly to the card?

Thanks!

 

[mobilenvidia]

1) Yes transparent

2) There will be a performance hit with SSD's on the expander, there is a little more latency, and depending on how many SSD's there will be a bottle neck via cable(s) to expander.
Using both SAS ports on the 9270 will reduce this.

Attach slow drives to expander using 1x SFF-8087 cable
Attach fast SSD's to other SFF8087 port on 9270 (max of 4x SSDs)
Best of both worlds.

 

[lunadesign]

Thanks....good to know.

With regards to #2, would you characterize the performance hit as small, medium or large?

I was planning on putting 4 SSDs in RAID10 on the onboard port and then putting a handful of HDDs on the expander. However, I may need another 2 SSDs in RAID1, in which case they would have to go on the expander. I'm curious how much slower those SSDs will be than if they had been connected to the onboard.