Q: XSAN and AFP Latency
I previously managed an XSAN hosted on 10.7 (upgraded originally from 10.5) and just destroyed that volume, to create a new xsan on 10.9 with new server hardware. We are running 4 computers on the XSAN. The transfer speeds are great via XSAN over fibre, but when one computer re-shares multiple folders living on the volume via AFP, there is a latency issue when streaming video from the server.
You can see a link below to watch the issue. It happens every 3-4 minutes while steaming video (I have cropped that out for you). Where you see the mouse move between 3-9 & 12-17s, there is a beach ball on the Mac.
https://www.dropbox.com/s/j81t5eoer3rmsxf/converted.mov?dl=0
There is a second link below that shows a screen shot of the Activity monitor for Network from the AFP client. You can see 3 instances where the download pauses for 5-6 seconds.
https://www.dropbox.com/s/2hblkg11exe31ng/Screen%20Shot%202014-10-22%20at%204.55 .54%20PM.png?dl=0
Details of the configuration are as follows:
4 computers on XSAN (2x Old Mac Pro, new Mac Pro trashcan, iMac).
XSAN includes two PROMISE volumes.
All computers (including AFP reshare clients) are running 10.9.5
XSAN works great via Fibre (over 800mb/s write and 3gb/s read).
Mac Pro, OS X Mavericks (10.9.5), Trashcan
Posted on Oct 22, 2014 1:58 PM
