The RAM helps a lot in a test like this, but you get the idea. Here's a 4GB dd on a similarly-spec'd system (D元80 G7 with 24GB RAM and a p410 with 2 x SAS disks and 1GB Flash-Backed Write Cache). You get the write confirmation to the application without having to incur the latency of the physical disk drives. The cache makes a tremendous difference in that writes are buffered by the cache memory before being committed to disk. The HP Smart Array P410 is a fine controller, but you will get poor performance out of it if you don't have the battery-backed or flash-backed cache units installed. Would very much like to know what you guys have to say of it, is it more likely to be a problem with the controller/disks or is it low performance because of budget components? I can't see a lot of disk activity in the infrastructure client, but I haven't been looking for causes or even tried diagnostics because I have a feeling that it's either because of the cheap raid controller - or simply because of the lack of memory for it.ĭespite the problems, I continued and installed a virtual machine that serves a key function, so it's not easy to take it down and run diagnostics. Tried both SATA and SAS disks and SATA disks are nearly unsusable, while SAS disks feels extremely slow. With windows 7, the vmware converter installation even timed out. This has been a problem from the start.As a test of the Opteron processor family, I bought a HP D元85 G7 6128 with HP Smart Array P410i Controller - no memory.Ģx146GB 15k rpm SAS + 2x250GB SATA2, both in Raid 1 configurations.Įven with one virtual machine only, tried Linux 2.6/Windows server 2008/Windows 7, the VMs' feel really sluggish. The server isn't very loaded and the VMware Infrastructure Client performance monitor is showing 550KBps average read and 1208KBps average write for the last 30 minutes (highest write rate: 6.6MBps). Timing buffered disk reads: 316 MB in 3.02 seconds = 104.79 MB/sec Timing cached reads: 6584 MB in 2.00 seconds = 3297.79 MB/sec Ns1:~# time sh -c 'dd if=/dev/zero of=ddfile bs=8k count=125000 & sync'ġ024000000 bytes (1.0 GB) copied, 282.307 s, 3.6 MB/sĬompared to another server those number are terrible: Dell R200, 2x 500GB SATA disks, PERC raid controller (disks are mirrored). Timing buffered disk reads: 18 MB in 3.79 seconds = 4.75 MB/sec

Timing cached reads: 3364 MB in 2.00 seconds = 1685.69 MB/sec The disk write performance is really bad. The disks are in RAID 5 (3 disks + 1 hot spare). I have a HP D元60 server with 4x 146GB SAS disks and a Smart Array P400i RAID controller with 256MB cache.

Hp smart array controller performance