Increased transfer speeds from PC to Cache drive!

[DoeBoye]

Hi folks,

 

Thought I'd post a little tidbit I learned today: I've always had transfer speeds hovering around 30-40MB/s between my PC and my unRaid server's cache drive. Though not terrible, I keep seeing people talk about average speeds in the 60s/70/80 MB/s, so of course, I had to wonder what was wrong with my setup...

 

I've always suspected that the source drive in my system may have been part of the problem, and sure enough, when I replaced the OLD 5400RPM (I think) IDE drive out of my PC with a slightly newer 7200 RPM SATA drive, I gained about 10 MB/s in transfer rate...

 

I've gone from an average of 30-40 MB/s to 40-50 MB/s. Still not bleeding edge, but a pretty solid increase. So, for anyone suffering slow transfer speeds, this may be a place to look...

 

Cheers,

 

DB .

 

[EDIT] Added 'cache drive' for clarity

[StevenD]

I get almost 40MB/s to my parity protected array.  But yes replacing older, slower drives certainly speeds things up.

[yelnatsch517]

Interesting... I was getting 90 to 100MB/s from a 1.5TB Seagate to a WD20ears over 200ft Cat6 and a switch.  This is without a parity drive, of course.  Now I TeraCopy to my unRaid with a parity drive at speeds between 25MB/s to 35MB/s.

 

Is the drive you're reading from the system drive?  My read drive is not the same as the one with my OS.  That might improve speeds as well.

[DoeBoye]

Nope. The system drive is a small SSD drive. The one that unRaid is reading from is purely for data.

 

I'm very curious to see what happens now if I put a faster cache drive in place. Currently using a WD EARS drive, but will have a new Hitachi 5K3000 cleared shortly. They seem to have slightly higher speeds then the EARS, so if it is the new bottleneck (The cache drive instead of the old IDE source drive), perhaps I'll see another slight jump in speeds...

 

 

DB

[DoeBoye]

So I just finished pre-clearing the Hitachi drive, and ran a disk speed test from unMenu, and am pretty impressed with the performance. Here's the output:

 

/dev/sda:

Timing cached reads:  3438 MB in  2.00 seconds = 1719.65 MB/sec

Timing buffered disk reads:  86 MB in  3.03 seconds =  28.37 MB/sec

 

/dev/sdb:

Timing cached reads:  3268 MB in  2.00 seconds = 1634.52 MB/sec

Timing buffered disk reads:  84 MB in  3.01 seconds =  27.87 MB/sec

 

/dev/sdc:

Timing cached reads:  3252 MB in  2.00 seconds = 1626.43 MB/sec

Timing buffered disk reads:  304 MB in  3.02 seconds = 100.77 MB/sec

 

/dev/sdd:

Timing cached reads:  3340 MB in  2.00 seconds = 1670.37 MB/sec

Timing buffered disk reads:  312 MB in  3.00 seconds = 103.95 MB/sec

 

/dev/sde:

Timing cached reads:  3514 MB in  2.00 seconds = 1756.97 MB/sec

Timing buffered disk reads:  286 MB in  3.02 seconds =  94.76 MB/sec

 

/dev/sdf:

Timing cached reads:  3314 MB in  2.00 seconds = 1657.43 MB/sec

Timing buffered disk reads:  298 MB in  3.01 seconds =  99.16 MB/sec

 

/dev/sdg:

Timing cached reads:  3286 MB in  2.00 seconds = 1642.85 MB/sec

Timing buffered disk reads:  318 MB in  3.01 seconds = 105.71 MB/sec

 

/dev/sdh:

Timing cached reads:  3312 MB in  2.00 seconds = 1656.41 MB/sec

Timing buffered disk reads:  300 MB in  3.02 seconds =  99.36 MB/sec

 

/dev/sdi:

Timing cached reads:  3332 MB in  2.00 seconds = 1666.22 MB/sec

Timing buffered disk reads:  322 MB in  3.00 seconds = 107.29 MB/sec

 

/dev/sdj:

Timing cached reads:  3334 MB in  2.00 seconds = 1667.11 MB/sec

Timing buffered disk reads:  306 MB in  3.02 seconds = 101.44 MB/sec

 

/dev/sdk:

Timing cached reads:  3328 MB in  2.00 seconds = 1664.26 MB/sec

Timing buffered disk reads:  276 MB in  3.00 seconds =  91.95 MB/sec

/dev/sdl:

Timing cached reads:  3280 MB in  2.00 seconds = 1640.15 MB/sec

Timing buffered disk reads:  412 MB in  3.01 seconds = 136.84 MB/sec

 

/dev/sdm:

Timing cached reads:  3318 MB in  2.00 seconds = 1659.37 MB/sec

Timing buffered disk reads:  296 MB in  3.02 seconds =  98.10 MB/sec

 

 

sdl is the new Hitachi drive. The rest are WD Green EADS and EARS drives, as well as a couple of older Seagate 7200RPM drives. Once my cache drive finishes transferring all the custom folder data over, I'm going to try the Hitachi as Cache drive and see if performance is affected...

[jeff.lebowski]

My cache is also an IDE model, WD 2500JB. It has hit as much as 50MB/s, but sustains 40MB/s. I'm happy with that most days. The protected array only sustains 25-30MB/s.

 

I'd like to use something that has better performance, but even when spinning, this IDE disk sits at 17-22C. I don't think any SATA disk I have can match it.

[DoeBoye]

I'd like to use something that has better performance, but even when spinning, this IDE disk sits at 17-22C. I don't think any SATA disk I have can match it.

 

That's a pretty cool running drive! What do your SATA drives run at while the IDE is at those temps? Is this a normal quality of IDE drives?

 

DB.

[neilt0]

I use a 2.5" 5400rpm laptop drive for my cache drive. 1W power consumption and up to 50MB/sec.

[Rajahal]

Normally IDE drives are much hotter than SATA drives.  I'm surprised at jeff.lebowski's results.

[jeff.lebowski]

I'll get everything running in a bit and post that, too.

[jeff.lebowski]

I guess I was wrong about the cache disk's temp. All disks spinning, copying to the cache disk: