my disk I/O is 100% all the time whatever the MB/s

hi - I've had this problem for some time and need to get to the bottom of it, because performance on my Samsung Series 7 laptop is nothing like what it should be. Disk access on the system appears to be very slow and severely impedes performance. the system is Windows 8.1, with a terabyte hard disk, Seagate ST1000LM024, 8gb RAM. In Task Manager, the third data column 'Disk' is almost always at 99% or 100%, literally all the time. The weirdest thing is though, ordering the applications by most to least disk usage, it doesn't seem to matter what the sum of each application's disk usage is ( including all the low-level stuff like System, the Windows indexer etc). In other words, if the aggregate transfer appears to be around 2 MB/s it may very well say 100%, at the same time if it spikes up to 20 MB/s it will still say 100% - clearly, both can't be correct. the Intel Rapid Management Software says that the SATA disk transfer rate should be 3 GB/s, that's GB/s not a 1,000th or so of that... I would be very grateful if anyone could shed any clues as to what is going on because my system is definitely much slower than I would expect, but does speed up in the occasional intermittent phases when Disk I/O percentage utilisation appears to drop to something more reasonable like 10-20% - these periods don't last long, and it is not clear what ends them. thanks
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Lee IngallsConnect With a Mentor Director of IT/TS, Quality and FinanceCommented:
That's why I asked about the various settings in X1... I ended up relocating my X1 index files to a secondary drive to remove much of the write over-head. There's still read over-head and the parsing of the index-able content based upon the "maximum amount of text extracted per item".
Tony GiangrecoCommented:
1. Open event viewer, look for system and application errors. Make sure your not having any disk errors.

2. Install Malwarebytes and Superantispyware and run full scans to determine if you have spyware or a virus.

3. Open my computer and let me know the size and free space of the drive(s).

4. If the drive is a replacement, provide the brand and model.

5. Assuming everything looks ok from those questions, defrag all partitions in My Computer. Properties( of the drive), tools disk maintenance

This will provide insight into what you are working with and what the current conditions are.
You should be able to open task manager and choose to view the I/O reads and I/O writes as display columns, once you can view those you should be able to see what is doing the reads/writes that are causing your disk utilization.
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Lee IngallsDirector of IT/TS, Quality and FinanceCommented:
You can look to see what is using the Disk I/O by opening your Task Manager and select the Details tab. Right click a column header and click Select Columns. In the Select Columns window... select I/O Reads, I/O Writes, I/O Read Bytes, I/O Write Bytes then OK.
Adrian_HarrisAuthor Commented:

ref TG-TIS:

1) spent a lot of time on this previously, didn't reveal anything
2) running Malwarebytes already, full recent scan, no substantive problems
3) 900gb drive, 110gb free but has been like this for a whole phase when a good 200-250gb was free
4) it is original drive, model number mentioned in original request
5) I thought manual defragging was no longer required from Win 7 onwards but I will give it a whirl overnight

ref jrm213jrm213:
1) thanks but I've already been doing that, and also comparing against Resource Monirot, which quite interestingly lags the data in the Task Manager by a few seconds on a consistent basis
2) the problem is that the numbers don't add up - put together all the apps and system processes which are doing I/O and a) they typically add up to only about 5 MB/s I/O yet somehow this is 100% of capacity which I find hard to believe and b) occasionaly they peak at higher levels for a short time, like 25 MB/s yet this is still described as 100% of capacity...?

ref Lee Ingalls:
thanks, I have also been working with Processes, gives the same results and in any event provides less useful in formation

Overall the point is that, what to me seems like a very small amount of <accountable> IO, e.g. 5 MB/s, whether as seen in Task Manager, Processes tab or same, or Resource Manager, seems to add up to 100% whether it 'adds up' to 5MB/s or 5 times as much..

It suggests to me that 100% of IO is plenty higher than 5MB/s and there is some process or other which is taking up IO without revealing itself through those interfaces. I am well covered on anti-virus etc, I'm 95% sure it's not a rootkit or something like that.

Another way of approaching this is:

- what IO rate is my Seagate drive supposed to have in a Win 8.1 system like this? 5 MB/s 50MB/s? I have no idea, does anyone else? all I can say is that the SATA disk controller has a massively larger data transfer rate of 3GB - is this relevant? if not, where can I find what rate my drive is supposed to be able to do? I have looked through the Samsung diagnostic/statusware and that's all it tells me... what's normal? it's a £1,000 Samsung laptop bought 6 months ago with Win 8 on it at the time.

Jackie ManCommented:
It is a known bug of win 8.1 on some old hardware and there is no fix (except to revert back to win 8)
Tony GiangrecoCommented:
If there is a diagnostics CD that came with the unit that is self booting and runs system wide tests, you might want to try that. Or possibly run diagnostics from the diagnostics partition if it has one.

You may have a HD controller that doesn't work properly.

You might want to run a full backup to be safe.
i would run a disk diag on ALL the drives, just to be sure they are ok
if needed - you can run the diag on another PC (a known good working one)
i use the UBCD for this  -it has all diags :
Hardware diagnostic CD    UBCD

go to the download page, scroll down to the mirror section, and  click on a mirror to start the download
Download the UBCD and make the cd   <<==on a WORKING PC, and boot the problem PC from it
Here 2 links, one to the general site, and a direct link to the download

since the downloaded file is an ISO file, eg ubcd527.iso - so you need to use an ISO burning tool
if you don't have that software, install cdburnerXP :

If you want also the Ram tested - run memtest86+ at least 1 full pass,  - you should have NO errors!
For disk Diagnostics run the disk diag for your disk brand (eg seagate diag for seagate drive)  from the HDD section -  long or advanced diag !  (runs at least for30 minutes)                        ultimate boot cd             download page
Gerald ConnollyCommented:
What files are being shown as the hotspots for disk i/o, use Resource Monitor to check that out
1. A note on my earlier post. When task manager is open and you are looking at disk utilization, make sure you have "View processes from all users" checked.

2. Your laptop doesn't happen to have drives set up in RAID does it. When a drive becomes degraded in a RAID setup it might not report it anywhere useful and it will severely slow down your machine.

3. Have you tried going to the command prompt and typing sfc /scannow ? If so what does it give you for a result. I recently had some files corrupted due to a windows update that caused me a lot of grief. I had to recover the damaged files from another installation.
Tony GiangrecoCommented:
Check your anti virus options. if it's set to check compressed files, this may be causing extended I/o. I've experienced that myself when elevating the protection in my AV app.

Did you run the System Diags test? Any results you can post?
Adrian_HarrisAuthor Commented:
thank you all - picking out a couple of these items, disk fragmentation was 0%, as you would expect on any system from Windows 7 onwards. With regard to the 'known bug'on 'old hardware', that wasn't my interpretation of the article I read. I would like to reduce this down to 2 very encapsulated questions for the time being - I attach 2 jpg files, disk usage 5.jpg and disk usage 6.jpg, each showing on the left-hand side the Processes screen of the task manager, and on the other side the Resource Monitor. In both cases I waited for a few seconds to confirm that the readings were not momentary spikes:

1) the left hand side of the screen in disk usage 5.jpg shows 'Disk' at 100% with an aggregate activity on it of approx 12.2 MB/s, whereas the same in disk usage 6.jpg shows an aggregate of 30.3 MB/s accounting for only 45% of (available?) disk I/O capacity - surely both of the readings cannot be true.. does anyone know the answer as to why these could nonetheless both be valid readings?

2) comparing the right hand side of the two screens, ie the Resource Monitor panels, with both sets of left hand data from above, we see nonetheless that in disk usage 5.jpg ( the one showing 100% disk utilisation in the Processes tab of task manager), there is a 'System' entry at the top of the list accounting for 2.3 MB/s (ignoring strict bits to mb conversion), and the entry for X1ServiceHost.exe ( which according to task manager is the highest ranking disk activity) totals a mere fifth of that or so. Compare that to disk usage 6.jpg and you see that X1ServiceHost.exe has about the same absolute level of I/O activity, but the 'System' entry (same PID '4' as per disk usage 5.jpg) has virtually no activity going on - and we observe that the task manager thinks disk I/O is only operating at 45% of capacity. Do we think the System entry PID '4' is the main culprit and that its true level of activity is much higher than the level being shown under the Processes tab in Task Manager? - and if so, how could such a fundamental reading not be showing up properly?

I think the nub of the issue lies in those two questions and would be grateful for any light you can shed on why I am observing what I am observing.

Gerald ConnollyCommented:
The Blue Line on the graph is IOPS, the green line MB/s

And it looks like the left hand side is showing the same thing.

The difference between the two applications is probably down to sample points and interval.
Lee IngallsDirector of IT/TS, Quality and FinanceCommented:
I use the X1 indexing service. What are your Index Priority settings? Never Delay (most aggressive), Delay x number of minutes or Never Index when computer is in use (least aggressive)?

Also, do you have index files in real-time enabled?
Lee IngallsDirector of IT/TS, Quality and FinanceCommented:
Additionally, what is your maximum amount of text extracted per item?
Minimum is 1MB

Keep in mind that disk utilization isn't just mb/s. If you transfer 1 very large file, lets say 5gb for example, you might get 30mb/s of disk utilization that also accounts for 45% disk utilization and it may only take a few minutes.

Now if you transfer 10,000 files that combined also equal 5gb, you might only get a 4mb/sec but be using 100% disk utilization and it may take 45 minutes to complete.

Basically there is overhead involved. Seek times, parity checks, etc. You almost never get the mb/s in read or write that drives claim unless your process is the only process and your date is the only thing being transferred. So it's completely possible for 9mb/s and 30mb/s to both be 100% disk utilization or one to be 45% and the other to be 100%.

It could very easily be the same with an indexing service. Reading and indexing a few large files vs. reading and indexing many small files.
jrm213jrm213Connect With a Mentor Commented:
Also, just because a SATA II connection can burst at 3gb/sec doesn't mean your hard drive or your computer can, i actually don't know if any mechanical hard drive can hit those speeds. I am not even sure that any SSD's can currently hit an actual 3gb/s transfer let alone 6gb/s. It would sure be nice if they could though.
Gerald ConnollyConnect With a Mentor Commented:
As i said the two different tools are displaying data from different sample points and timebases, hence the difference.

@JRM you are right its hard for devices to fill all of the pipoe so a 3Gb/s device can talk on a 3Gb/s bus, but probably cannot get anywhere near that speed when doing transfers. SSD typically do not do much better at MB/s than a spinning disk Disk @200MB/s, SSD @500MB/s, BUT they do far greater IOPS, whereas a spinning disk can only do 200 IOPS max (15K Enterprise class disk) a SSD can do thousands of IOPS

NB IOPS and MB/s are mutually exclusive, ie for a spinning disk its either 1 * 200MB = 200MB/s, or 200 * 1MB = 200MB/s
Adrian_HarrisAuthor Commented:
thank you all - I figured we might get into this sort of area, but actually I learned a bit and can accept that at first glance discrepancies between the stats. Overall I suspect X1 is the culprit (thanks Lee), it has a LOT to index and it does about 70% over a corporate network so that isn't going to help either. Having said that, I have recently found that closing Outlook will take disk activity back down to normal levels, but this is probably because X1 was attempting to digest multi-gb mailboxes whilst it was open. thanks for your help.
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