"Disk overloaded 100%" ~ Why?

Lately I cannot seem to download anything without µTorrent constantly doing this thing where it decreases all my speeds to less than 10kB/s and displays "Disk overloaded 100%" in the status bar.

µTorrent apparently needs to be restarted to return to normal. However, when this happens, µTorrent will not close properly. If I attempt to close µTorrent, the application will disappear, but the task is still running; I must force close it.

This issue seems to occur even if I have only a total of one active torrent.

My download bandwidth is set to 1024kB/s, and upload is set to 128kB/s. My hard drives are both SATA, capable of up to 3gb/s. I am running Vista SP1; µTorrent version 1.8.3 (build 15772).

Recently? Have you changed anything recently? Defragment your drives.

My only recent changes are as follows:

• Upgraded ISP account for more bandwidth. -- Approx. 2 weeks ago

( Bandwidth limits are set in µTorrent, so this shouldn't be a factor. )

• Upgraded RAM (2 GB to 6 GB). -- Approx. 1 week ago

( Technically this shouldn't be a factor either... =/ )

I am not exactly sure how long this has been going on for, and I can't think of any other changes to my computer or network than what I listed.

As for defragmentation: My hard drives are scheduled to do this daily, so they should already be optimized in that aspect.

If you're on Vista, are you using the built in defrag? Try that if you aren't. Also watch for at what speed it happens and what the disk cache is doing, tweaking the disk cache may help.

Also, many SATA drives wont even reach 1.5 Gbps while bursting, the drive you have is one of many factors.

Yes, I do use Vista's built-in Defragmentation program; it is scheduled to run a defragmentation on all of my hard drives every morning.

Also, I built my own computer, so I do know that my motherboard and hard drives are all capable of 3.0gb/s. And before anyone asks, yes, the HD pins are configured correctly to enable 3.0gb/s speeds, rather than being limited to 1.5gb/s.

When this issue occurs in µTorrent, there is very little activity amongst the hard drives. It would be difficult to monitor µTorrent in attempt to figure out what exactly happens before this error occurs, as it seems to occur rather randomly.

You could probably test/trigger the condition using the test torrents mentioned in the 1st link of my signature.

A hard drives cache might be capable of 3Gbit/s, but the disks themselves wont be even close, maybe 1/3 of that at best ~100MB/s, and thats all sequential, which BT is not.

diskio.no_zero set to true? Are you scanning for viruses and defragmenting and extracting archives in the background at the same time when you get the 100% overload?

Have you specified a cache of say 1000MB manually and tried with that? (you do have the RAM for that and much much more)

I've been getting this regularly lately with my external 2-bay HDD storage. Basically, since the two HDD:s share the same USB case and cable, there is some intrinsic latency in the way the connection is managed to separate between the two drives, so you have to wait up to a second longer when accessing either of the two disks than you would have had to with a single external HDD.

I have no problems downloading stuff from the Internet onto these disks at very high speeds, nor do I experience issues when copying local files to them at even higher speeds. I can even download a few medium-sized torrents on one of the disks with no problems and with decent speed.

However, when I download even a single torrent greater than let's say 5 GB, the disk immediately gets overloaded even when I'm downloading at ridiculously slow speeds of a few kB/s. And just like some mentioned here, uTorrent stop being responsive and I even have troubles terminating the uTorrent process. When I finally manage to shut it down, I have to re-check the torrents and then when I restart them they immediately get overloaded again, and this behaviour repeats itself in a loop. Obviously, a big torrent requires uTorrent to continuously access a wide portion of the HDD making the time-lag that I mentioned to be of crucial importance since you get that lag for each and every new HDD access.

The advice of increasing the cache size that's been discussed here did in fact resolve the issue partly in my case. Basically, the cache gives uTorrent and the HDD some venting room so that they can catch up with each other and until they catch up with each other uTorrent keeps loading the contents directly into RAM in order to keep the HDD in the game. Obviously, too many (big) torrents will create a spiral of more RAM being consumed as cache than the HDD is able to digest, inevitably leading to a crash.

So, the trick is to find a sweet-spot between the RAM cache size and the number of torrents your system can handle with a cache of that size. In my case, by trial and error I've found that my external HDD:s now can handle 3 big torrents (big as in 10-30 GB) while remaining safely below the RAM cache threshold (first the RAM bulks up, then when the HDD catches up it decreases). Just one more big torrent, however, and a crash becomes inevitable. This is not a perfect solution but now I can at least download a few big torrents to my HDD:s which I wasn't able to do before. Thanks for the tip