March 8, 201610 yr Hi, I have just installed the latest V6 standard as a trial and am using the following config Parity WDC_WD20EADS-00S2B0_WD-WCAVY2344157 - 2 TB (sdb) 37 C 77,934 77,061 0 Disk 1 SAMSUNG_HD204UI_S2H7J90B309594 - 2 TB (sdc) 29 C 93,994 77,021 0 xfs 2 TB 845 GB 1.15 TB Browse /mnt/disk1 Disk 2 SAMSUNG_HD204UI_S2H7J9AZC01502 - 2 TB (sdd) 26 C 208 37 0 xfs 2 TB 33.8 MB 2 TB Browse /mnt/disk2 The problem I have is that from idle, when I start a transfer I get 60-80mbp's for a minute or so but then it drops to 19-23mbps permantly for the rest of the transfer.. is that normal? seems very very slow! Many Thanks
March 8, 201610 yr Community Expert Assuming you’re transferring large files (500MB+), it seems on the low side for your disks, although because of how parity works in Unraid it will never be as fast as single disk or raid5/6, initial transfer is cached to RAM, when RAM fills up you’re limited by the actual HDDs speed, with those disks I would expect 40-45Mb/s, two things you can try: Diskspeed – check that your disks are performing as expected Turbo write – since you only have 3 disks and if you don’t mind them spinning all up for writes, it should be at least twice the speed.
March 8, 201610 yr Author Many thanks for your reply, unfortunately after reading through both the threads you sent me, nowhere is it written how to install diskspeed or how to enable turbo write? Does anyone else here use an N36L to give me a guide as to what speed I should be getting? Thank you
March 9, 201610 yr Community Expert In my experience the disks used have the most impact on Unraid write speed, I have several microservers, model N54L, but expect the N36L to be similar: Using late model 5400/5900RPM disks, e.g, WD Green, Seagate Archive: up to ~60MB/s Using late model 7200RPM disks: up to ~80MB/s Using older slower disks like yours: 25 to 45MB/s Note that speed will be always limited by the slowest disk used in the operation, in normal writing mode, parity and the actual disk being written to.
March 9, 201610 yr You won't get 80MB/sec writes to the array. I get around 40MB/sec on my N54L, maybe a little faster with an empty drive. I'm due to re-add a 7200rpm warranty replacement drive soon, so I'll post speeds when that's in.
March 9, 201610 yr Author thanks for the reply, I built another system last night from old bits I had lying around, here is the spec Model: Custom M/B: Gigabyte Technology Co., Ltd. - G41M-ES2H CPU: Intel® Celeron® CPU E35 @ 2700 HVM: Enabled IOMMU: Disabled Cache: 64 kB, 1024 kB Memory: 4096 MB (max. installable capacity 32 GB) Network: eth0: 1000Mb/s - Full Duplex Device Identification Temp. Reads Writes Errors FS Size Used Free View Parity ST2000DL001-9VT156_5YD3AMRG - 2 TB (sda) 34 C 248 5,099,631 0 Disk 1 WDC_WD20EARS-00MVWB0_WD-WMAZA1411511 - 2 TB (sdb) 29 C 5,094,019 51,430 0 xfs 2 TB 33.8 MB 2 TB Browse /mnt/disk1 Total Array of two devices 31.5 C 5,094,267 5,151,061 0 2 TB 33.8 MB 2 TB The Parity disk only took 6 hours to build on this system instead of the 27 hours on the N36L!! I am getting 45 MB/s Write & 60MB/s read on this test system compared to 20ish MB/s write & 80MB/s read on the N36L so the write is faster on the test system but the read is faster on the N36L ?? I need to do some speed testing on the drives outside the box on my desktop PC maybe to understand which drives give me the best performance as I have 10 or so spare SATA disks here. I also have had some CRC Mismatches (using Teracopy) when moving files around on the N36L so maybe there is a deeper problem? if I re-copy/move the failed files they pass the 2nd time?
March 9, 201610 yr Community Expert The Parity disk only took 6 hours to build on this system instead of the 27 hours on the N36L!! This is too long for a 2TB array, probably something wrong with N36L or the disks used. I am getting 45 MB/s Write & 60MB/s read on this test system compared to 20ish MB/s write & 80MB/s read on the N36L Write speed looks normal for the disks used, read is usually limited by the disk speed. so the write is faster on the test system but the read is faster on the N36L ?? I need to do some speed testing on the drives outside the box on my desktop PC maybe to understand which drives give me the best performance as I have 10 or so spare SATA disks here. Diskspeed I linked above is very good for this, just copy the file to the root of your flash drive, SSH into Unraid (or use the console) and type: /boot/diskspeed.sh Avereage speed will be displayed but it will also generate the file diskspeed.html on your flash drive with a graphical representation of all disks speed. I also have had some CRC Mismatches (using Teracopy) when moving files around on the N36L so maybe there is a deeper problem? if I re-copy/move the failed files they pass the 2nd time? This definitely indicates a problem.
March 9, 201610 yr Sounds like one of the drives is attached to port 5 or 6 and the SATA unlock firmware has not been flashed. You can find more info in the thread in my sig.
March 9, 201610 yr Author Hi, Yes it has been flashed, did that years ago whilst running WHS on the server but I was not connected to those ports anyway, used the main caddies at the front. I have scrapped the plan now and built a 12 disk system (currently on trial 3 disk version though) using an ASROCK H77 PRO4/MVP (8 on-board SATA) 9GB RAM and a G1610T CPU from my Gen8 Microserver Using a WD20EADS Disk as Parity (fastest of the lot I have here) Currently reporting 4hours 40 mins to build the Parity drive which is the fastest I have seen so far from my 3 builds. Looks like this will be the way forward, seems a shame that the N36L is not a viable solution for me, something else to put to the back of the cupboard but then it only cost me £80 brand new many years ago! I have more than had my moneys worth out of it!
March 9, 201610 yr My parity build this week for 6x 4TB drives took 11.1 hours on an N54L, which is about right.
Archived
This topic is now archived and is closed to further replies.