Possible bug with large write cache filling up

[kalua]

I notices some system sluggishness under the following conditions:

Disk 1 is a HW RAID-0 array on an Areca controller, and very fast (4 Samsung 830 256GB SSDs). No FC.

Disk2 is a standard WS 2TB WDEARX disk with 5GB of FC with writeback on Intel mobo controller.

When doing a large (200+GB) copy from the RAID array to disk 2, naturally the reading is much faster than the writing, and the FC write cache fills up on disk 2. At this point the response of the system becomes very sluggish. Mouse is jerky, apps don't respond smoothly.

Anyone else seen this?

[support]

What's your Windows OS? and your total insalled physical memory?

[kalua]

WIn 7 x64, with 32GB RAM. (4x8GB)

[support]

Perhaps you may try a smaller Defer-Write latency. Too much "Urgent Write" will lower the write speed.
Also you may check the system available memory while copying to make sure that the issue is not caused by the low memory.
Thanks.

[kalua]

System memory was about 20GB used, (including FC cache) and10GB free.

I will try lower latency time. I have also moved the destination drive to the Areca controller, and off the Intel mobo.