Incredibly slow disk access under WinUAE 2.0.1

I just upgraded to the newest version from 1.61 and under my main Workbench config I'm getting incredibly slow disk accesses. However, if I lower the cpu idle slider 1 notch everything goes back to normal. By slow I'm referring to it taking several seconds to open the Prefs drawer versus nearly instantaneous before.

My system is an Athlon 64 3200 with 1gb of ram running XP SP3. I'm attaching the config file I'm using.

Ok, a little more info. I've discovered that when the WinUAE window doesn't have focus(and therefore the priority drops) the speed improves dramatically. For example, DiskSpeed goes from 11 file creates to thousands.

[NewDeli]

in Display tab / Settings / Native mode, I noticed vSync is activated when I loaded your config. Try choosing another (non vSync'ing) mode.
Also, just to make sure, I would leave refresh rate to default, and may be untick NTSC in chipset (even though you live in a NTSC country).

[Kyon]

i think its a bogus bug . isnt it ?

[dlfrsilver]

Originally Posted by Shnoober

I just upgraded to the newest version from 1.61 and under my main Workbench config I'm getting incredibly slow disk accesses. However, if I lower the cpu idle slider 1 notch everything goes back to normal. By slow I'm referring to it taking several seconds to open the Prefs drawer versus nearly instantaneous before.

My system is an Athlon 64 3200 with 1gb of ram running XP SP3. I'm attaching the config file I'm using.

Ok, a little more info. I've discovered that when the WinUAE window doesn't have focus(and therefore the priority drops) the speed improves dramatically. For example, DiskSpeed goes from 11 file creates to thousands.

Please test now : it should be better :

[Toni Wilen]

You mean "below normal" = no slowdown but "normal" = slow?

in Display tab / Settings / Native mode, I noticed vSync is activated when I loaded your config. Try choosing another (non vSync'ing) mode.
Also, just to make sure, I would leave refresh rate to default, and may be untick NTSC in chipset (even though you live in a NTSC country).

Yeah, I've been disabling vsync everytime I load the config but for some reason I've never resaved the config with vsync disabled. Actually, with vsync enabled it won't even get to the Workbench screen.

Please test now : it should be better :

No, all that does it put it into cycle-exact mode and disable Picasso96.

You mean "below normal" = no slowdown but "normal" = slow?

Normally I use "above normal" when active but I've tried it with normal too. I've done more testing and discovered that it starts out slow, then gets fast when I switch away but when I switch back it seems to be staying fast. I've been examining the process with Process explorer and it looks like at first only 1 thread is getting any cpu time but when I switch to a different process another WinUAE thread starts getting some cpu time and it doesn't give it up when I switch back to WinUAE.

I just tested with 1.6.1 and the second thread starts getting some cpu time right from the start.

[Toni Wilen]

Logs please (both logs, don't forget logging checkbox in misc panel). Also test with below normal.

[dlfrsilver]

I don't understand then because i have no slow problem here.

There has been many enhancements and bugs removed by toni in this version 2.0.1.

What kind of configuration are you using ?

[Toni Wilen]

This has been reported long time ago but lowering priority has always "fixed" it.

Problem has never been found, one possible suspect is real time virus scanner.

I did a quick test. Below normal still showed slow speeds but low worked correctly.

[Toni Wilen]

Do you have any virus/spyware/etc with real time scanning enabled? Does filesystem access still run slowly if it is temporarily disabled?

No virus/spyware or any other kind of scanning. Have other single core users reported problems or am I alone?

[NewDeli]

Can you try "unpacking" the HDF ? I mean trying with a Workbench barely located in a directory of your HDD. Also, did you install the latest VIA chipset drivers ?
Seems like a tricky issue.

[Toni Wilen]

Try http://www.winuae.net/files/b/winuae.zip (using normal priority first)

[Kyon]

Toni its a real bug ?

[Toni Wilen]

Originally Posted by Kyon

Toni its a real bug ?

No, it is caused by differences in Windows task scheduler priorities between versions and service packs and cpu types..

[Kyon]

Oh thanks

Sorry, it's still not working right. I'm starting to wonder if it's not my system which is why I asked if other single core users had reported the same problem. I've noticed that my cpu isn't hitting 100% all the time even though WinUAE says it is and to me that sounds like a problem on my end. In fact it seems to be dipping a few percent whenever disk access is supposed to be happening. This motherboard is a real POS. I would test on my other system but it's currently hard drive-less.

[Toni Wilen]

It could be powersaving problem but afaik it was common problem only with XP and AMD dualcores. Have you tried this: http://support.microsoft.com/kb/895980

Also, to 100% confirm it isn't priority issue, download Sysinternals Process Explorer, select winuae.exe process, open Threads tab.

First item in Threads tab should always have lower Base Priority than other winuae.exe threads (1 unit lower if using 1.6 or 2.0, 2 units lower if above beta)

I set all the WinUAE priorities to normal so I could switch back and forth with PE without it changing priorities. With 2.0.1 the top thread has a base priority of 8 and the other threads have a priority of 9. With the beta the top thread has a priority of 8 and the other threads have a priority of 10.

Even though the pmtimer switch is only supposed to affect dual cores I'm going to try it anyway to see if it has any effect.

Update: I just tried the /usepmtimer switch and no change.