Overclock.net banner

81 - 100 of 125 Posts

·
Premium Member
Joined
·
3,111 Posts
Quote:


Originally Posted by AzzKickr
View Post

Just wanted to say that short stroking is not just creating a small partition for the OS on the beginning on a large hard drive but defining block sizes and formatting in low level.

With a proper short stroked drive you cannot acces the unused space in any way, it will not even be visible in partition managers.

http://www.tomshardware.com/reviews/...-hdd,2157.html

That's one way of short-stroking, using a RAID controller and a drive manufacturer low-level formatting utility... however just using Disk Management or other formatting program to format the drive to a smaller capacity then the maximum performs the same function.

Access times... If they were not important why would anyone buy an SSD?

Also they make it easier to understand IOs/second
Basically the hard drive head has to physically move to each file you would like it to access... Some files are fairly small and are wholly contained in only a few sectors... with these small files, the access time plays the majority role in the amount of time required to read/write them

DISCLAIMER: all the numbers quoted here are pulled out of thin air as an EXAMPLE... use benchmarks to measure your actual drive.

So for example, if a program or the operating system needs to read/write 100 small files, then it will need to move the hard drive head around 100 times to access all those files

so 100 x say 12ms (avg hard drive)
1200ms
1.2 seconds

Say those files were each less then 4KiB
In this case, the hard drive has spent 1.2 seconds reading/writing 400KiB of data...
so 0.4MiB/second

That 300MB/second SATA interface is not looking like so much of a bottleneck now is it?

However, say you're reading a 1000MB file...
In this case there is 12ms to access the start of the file... then at say 100MB/second about 10012ms (10 seconds) to read the whole file... so for a SEQUENTIAL file, the MB/sec number is important...

However the average *size of files* on your drive is probably significantly less then 1000MB, probably less then 100MB.

Also this means that RAID arrays, however impressive MB/s numbers you get, the access times are not reduced from a single drive...
so that 4KB file still takes 12ms to reach

however with Short-stroking, the access time can be reduced! which means the majority of files on (say an OS or app drive) are significantly faster to access, which is why a short-stroked drive "Feels" faster since the response time is much better...

Remember my example with 100 small files:
at 8ms that's only 0.8seconds... a huge difference from 1.2 seconds, bringing the drive speed to 0.5MiB/second (for random small files)

Why are mechanical drives faster then 0.4 or 0.5 MB a second, (I think maybe 0.9 or so in 4KB random benches)

Well it doesn't always take 12ms to access the next file, sometimes the files are close together on the drive...
12ms would be the "average" seek time..

And while i've got some of your non-TL;DR azzez still reading, this is why Defragmentation also reduces access time, if that small file is in 4 pieces then it takes 4 strokes to access it....

And imagine 0.1ms access time, pop quiz anyone actually read this, post time taken to access 100 x 4KB files, and the total "MB/s" to read them
 

·
Premium Member
Joined
·
3,111 Posts
Ok Access times again... in an analogy

The files are notebooks, the hard drive is a house, and the read head is the person.
The person could be a quick reader/writer (fast sequential MB/s) and get good numbers sitting at the desk in the study with a large notebook...

However say she is a slow runner, and needs to access a notebook in the bedroom... The time taken to run to the bedroom and open the notebook is the access time (seek time)

So for example, if you closed off most of the house, and the reader/writer moved into only the lounge and moved all the notebooks into the lounge then it's the equivalent of short-stroking... Less time spent running around the house trying to get to each notebook...
 

·
Registered
Joined
·
2 Posts
Hi,
one Question.

Sorry for my bad language but still learning using better english.

Short stroke means that i reduce my capacity of the hard drive or using a part of my hard disk.
Does it function if i have a 1,5TB Hard Disk, creating a 40GB Partition first and than let the rest unformatted? I want to use Truecrypt for crypt my data, and you cant see there is a formatted drive. You have to mount it first and than access to it. So its shown in Windows as unformatted but having data on it. I would mount the greater part if i want to my data, and than it is not important for me, if THAN the transfer-rates and access time would be bad because of using the whole hard disk.

But if im using Windows i would not mount it, and so i would only use the 40GB partition. Is THAT short stroke or im shaking things together?

Gz
UncleHitman
 

·
Premium Member
Joined
·
4,496 Posts
Discussion Starter · #84 ·
That would effectively be short-stroking, yes.

The OS is only going to try and use the partition it can see. The only time you would access the other portions of the disk is when you access data on the truecrypt volume.
..a
 

·
Registered
Joined
·
2 Posts
And how can i measure it?

HDTune can handle but only if you click on Short Stroke. If i make 1 Partition 40GB with which Tool i can see the difference?

And how can i set the Partition in the front of the HDD? I used the Windows 7 Partitioner to create a 40GB Volume, is this enough or should i use a special tool for it?
 

·
Registered
Joined
·
2 Posts
First off, I personally believe there would be a gain by stroking a drive, as would be if you partition a drive as well. A procedure I have done since the mid nineties.

Now this is for "grunion"
First off, thanks for posting that pic, it has explained more of what I intend to do with a system build I am collecting parts for. Especially as the two motherboards I have narrowed down to purchase, both use the Intel RAID controller, the ICH10. I have been doing a crap load of research as it's been years since I ran RAID so for times like this, I can ask specific questions.

I noticed "grunion", that all your stripes are 128. Is it possible to run different stripe sizes and further more, any advantage to do so. I am aware that a lot of this depends on how the User, myself, intends on using the RAID array.

And I noticed we think alike, as I intend on doing three stripes myself as a way to organize by access priority.

Now I have directed these questions to "grunion", but all replies are welcome as I am here to learn.

Thanks in advance.

Hoggy
 

·
Premium Member
Joined
·
25,202 Posts
Quote:

Originally Posted by Roadhog View Post
First off, I personally believe there would be a gain by stroking a drive, as would be if you partition a drive as well. A procedure I have done since the mid nineties.

Now this is for "grunion"
First off, thanks for posting that pic, it has explained more of what I intend to do with a system build I am collecting parts for. Especially as the two motherboards I have narrowed down to purchase, both use the Intel RAID controller, the ICH10. I have been doing a crap load of research as it's been years since I ran RAID so for times like this, I can ask specific questions.

I noticed "grunion", that all your stripes are 128. Is it possible to run different stripe sizes and further more, any advantage to do so. I am aware that a lot of this depends on how the User, myself, intends on using the RAID array.

And I noticed we think alike, as I intend on doing three stripes myself as a way to organize by access priority.

Now I have directed these questions to "grunion", but all replies are welcome as I am here to learn.

Thanks in advance.

Hoggy
Bump for the block size question.
IDK the answer, set it and forget it, that's me

I've never compared the performance differences between block sizes.
 

·
Registered
Joined
·
2 Posts
The reason I am so curious about stripe size is as follows:

I am thinking of doing a 60 meg stripe at 64, this will contain only my OS, period. Next would be a 300 gig stripe at 128. And the third stripe to be all remaining space for archive files set at 128 as well.

The smaller stripe means more blocks to scan, but I have to wonder with a 60 gig and only OS, if this would work to my advantage.

But the huge question is, can I use different stripe sizes. If not, then the rest is just a moot point.

Hoggy
 

·
New OCN got me like...
Joined
·
4,097 Posts
Sorry to open this super old thread, but just wanted to say thanks and I'll be trying this when finals are over! Anything to improve boot up time =)
 

·
Registered
Joined
·
141 Posts
Nice write-up.
I noticed the second image says it's in Raid 0, the first one doesn't..
So, did you make a small partition and[ put it in raid 0 for the 'faster' example?
No offense or anything, but it doesn't seem like legit results unless both examples are in Raid0, or neither are.
 

·
Registered
Joined
·
2 Posts
Hi all, thx for the informative posts. I have a seagate 500gb 7200.11 hdd which i want to install my OS on and i have a wd 1.5tb green for storage,games and non essential programs.
I am going to do a fresh install of windows 7 on my 1tb seagate, so do i short stroke it before the install itself or during? Sorry I dont know much abt raid n stuff. How and when can I short stroke my 500gb seagate? Do i have to use the bios? So wat would be a good/optimum size to ss a seagate to? I dont really need so much space for os n programs actually, 25gb-50gb sufficient.

Very sorry if I am asking questions alrdy answered, thx for putting up with me.
 

·
Premium Member
Joined
·
4,496 Posts
Discussion Starter · #96 ·
That belongs in its own thread, but you say you have a 500GB and a 1.5TB, and you want to install on a 1TB?
I assume you mean the 500GB..

If you want to short-stroke the 500GB, you simply tell windows to create a smaller partition on the drive during installation. If you can live on 50GB (I'd suggest going to 64GB to give you a little breathing room) just allocate that much when Windows installation asks how large you want to make the partition.
..a
 

·
Registered
Joined
·
2 Posts
Quote:


Originally Posted by eflyguy
View Post

That belongs in its own thread, but you say you have a 500GB and a 1.5TB, and you want to install on a 1TB?
I assume you mean the 500GB..

Yup I mean 500gb, sorry for not starting a new thread, not too sure of thiw forum's posting culture.

Quote:


Originally Posted by eflyguy
View Post

If you want to short-stroke the 500GB, you simply tell windows to create a smaller partition on the drive during installation. If you can live on 50GB (I'd suggest going to 64GB to give you a little breathing room) just allocate that much when Windows installation asks how large you want to make the partition.
..a

Thx for the quick reply, I will try 64gb then. Not much of a difference between 50 vs 64gb then?
 

·
Premium Member
Joined
·
3,111 Posts
Quote:


Originally Posted by jana999
View Post

Yup I mean 500gb, sorry for not starting a new thread, not too sure of thiw forum's posting culture.

Thx for the quick reply, I will try 64gb then. Not much of a difference between 50 vs 64gb then?

Well the closer to you get to the middle of the disk the slower it gets, so you could short stroke to 400GB but the gains would not be that impressive... 10% is a bit extreme, but will result in good performance, 100GB is 20% short stroke... so 64 is an odd number but anything would do, you could even choose 75...
 

·
Registered
Joined
·
338 Posts
Thanks for the thread! It's the reason I decided to short stroke my Spinpoint F3.
I have only a single drive and two partitions set up, one for OS and one for storage. My short stroke partition doesn't show up in the HD Tune dropdown, so I just checked Short Stroke and here are the results:

Without short stroke:


Short stroked partition:
 
81 - 100 of 125 Posts
Top