Basil Chupin wrote:
On 29/03/13 16:05, Linda Walsh wrote:
Basil Chupin wrote:
OK, I'll go checking what performance one can expect from ntfs-3g but if it worked in USB 2 conditions then why shouldn't it work in USB 3 conditions?
Thought you said it was SATA-3?
I did. The internal HDDs are all SATA3. The external HDD is USB3.
Try measuring the "raw" disk READ times...(without any file system)... that should tell you how fast the disks can go w/o FS overhead. time dd if=/dev/sda of=/dev/null bs=16M count=256 --- that will do a raw read... Note if you read from a partition /dev/sda1, /dev/sda2... The higher numbered partitions will likely be slower (assuming (spinning hard disks) and not SolidStateDrives/SSD). Don't get your if (inputfile) and outputfile backwards on a read test... it can write garbage to your HD...(prolly know that, but I've made real bonehead mistakes before, so good to pay attention!)...
Anyway, you might try mucking around in proc
first you might try lowering /proc/sys/kernel/sched_latency_ns to 10,000,000 (enter it w/o the commas) ..
That's now set to 24,000,000 so you suggest lowering it to 10m - OK, will try later.
---- Yeah, that's what mine is--- I think that's normal ... you probably (am really guessing, but that likely means you have a 1000Hz clock. 24000,000 = 24ms = 24 ticks of a 1000Hz clock. Was just seeing/experimenting if a lower latency on switching might give you any better response in switching between kernel and user space (since you mentioned you were using the user-space NTFS driver). Everytime they switch there's more overhead... But, just a thought (or theory), that lowering the scheduling time-slice might help them switch back and forth more quickly -- (but I might be having you tweak the wrong value -- but don't worry -- it will reset when you reboot or just cat 24,000,000 into if you wanna put it back...
(Aside: "What's 'running tickless'?! Nevermind.....it's gotta be computer talk-type jargon...." :-) .)
Sorry, I never know how much the person I'm talking too knows, didn't mean to sound too techy....I can explain things to my mom and she's in her 80's!... so I have a bit of range....
[pruned]
That might give you a few things to try... ;-)
That's it? That's all there is for me to try? :-D
---- Well, if you really want more.... ;-) Just thought those might give you some solid numbers. I regularly use 'dd' for fastest-speed tests.
But joking aside, thanks for your response - it's really appreciated.
No prob -- understand the overload -- take it slow -- read up on what they do, it's the way to learn -- pokin around and exploring... -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org