Windows: Line-Based vs. Message Signaled-Based Interrupts. MSI tool.

Intel RST drivers enable MSI-mode by default.

 

I tried to read this wall of text ,but gave up after 2nd line.

 

interesting read. I have changed most of my thing to msi mode but didnt notice any improvments.

 

Me either on the powerful home rig, but on the weak work rig I did notice improvements.

 

MSI is the older version . (nobody should have this active in any shape or form if they have pcie )
we say MSI but the truth is MSI is the initial version when we were leaving IRQ)what we use today is msix.now I probably confused you! I don't know how to do msix in : xp,vista,w7 .here is how w8 is tho .msix various setting can be set in power she'll .as far as I know only w8 + do this or w8 has different naming command in powershell for msix in w8 ..msix it self would need a thread for its self .but msix is what is mandatory for pcie .msix is the default so you have to disable MSI if you manually settled it in regedit.MSI tweak is intended only for device using IRQ but that do support MSI.I would have wrote the power she'll way for msix and call it a day ! WHAT IS POWERSHELL? I know a bit in computer but powershell is a new thing I ll have to learn .

PS:msix is not a speed tweak .it is more like a smoother of path.very useful if you stream on twitch ,while viewing YouTube while playing battlefield 4 while recording everything.in order for this to become a speedup buffer need to be disabled since it is no longer required since msix is properly set.if any know the powershell command ? . the trouble ? command for an i5 2500k optimal MSIx . the trouble ? as you obviously saw a lot of hardware maker dont go to the trouble of setting MSI or msix and still use IRQ . and as you obviously saw cause countless problem. hopefully this more elaborated version will answer a lot of question you guys had

 

@drbaltazar
I suspect you are wrong:

Code:

A solution to all these problems is a new interrupt mechanism first introduced in the PCI 2.2 standard called message-signaled interrupts (MSI).
...
Finally, MSI-X, an extension to the MSI model, which is introduced in PCI 3.0, adds support for 32-bit messages (instead of 16-bit), a maximum of 2048 different messages (instead of just 32), and more importantly, the ability to use a different address (which can be dynamically determined) for each of the MSI payloads.

From http://www.ni.com/white-paper/3767/en :

Code:

PCI 2.2 introduced an alternate method of propagating system interrupts called message signaled interrupt (MSI).
...
The PCI Express specification reuses the MSI concept as a primary method for interrupt processing and uses a message space to accept all prior sideband signals, such as interrupts, power-management requests, and resets, as in-band messages.

For me all that means that PCI-Express is natively uses MSI-X mode. And not supporting it in OS` like Vista and 7 looks strange for me.

 

I could be wrong since I didn't know interrupt played such a crucial role in our system till a about when I discovered the thread here .I know one thing .msix is mandatory on newer system .since all this is probably only seeable in powershell (ya I use window 8.1 )I all have to learn powershell .its the second time I meet setting I have to do in powershell.arrg.

 

removed sorry guys !

 

Actually I have encountered some strange problem. After I changed most of my thing to msi mode I get random clicks in audio playback. Then I use latencymon and the latency was higher than before.


Before the highest DPC routine execution time was only about 330us by nvidia. Now its like other device is starving for resource because they are all in msi mode

edit: nvm its the TCPNoDelay=1 making my nic crazy. Deleted the key and its fine now.

 

Wow, LatencyMon v6 !

 

how you have Intel USB 3 I thought they didn't have one . also you might want to use Intel sata raid thingy if you can .even tho its says raid it will detect single drive and its MSI so it should leave IRQ for other thing . is there a big performance difference between latencymon 5 and 6 (less latency hopefully .last week my test with v5 showed it among the most latent!

 

I have intel RST its at the irq -15

 

oh if you have rst then your are good !

 

http://msdn.microsoft.com/en-us/library/windows/hardware/ff544246(v=vs.85).aspx
follow these instruction in combination with what this thread say and you should be fine
one thing tho !
look here to find your own value for each msi you ll change
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\PCI\VEN_8086&DEV_244E&SUBSYS_844D1043&REV_B5\3&11583659&0&E7\Device Parameters\Interrupt Management\Routing Info\static vector
if you just enter the value ms exemple give it cause error at time ! aside from this ? everything looks like it is working perfectly ! MessageNumberLimit didn't do much for me but I suspect its because I don't have enough demend interrupt wise .probably affect nicely streamer recorder youtuber all doing this at the same time . since I don't multitask it doesn't affect me as far as I can tell .I set it any way just in case !

ps : my registry is just an exemple , yours will be similar beginning and end but the name will be different !

 

Any know how to verify if I am using 4 interrupt (1 per core! ) also ,how come some stuff can't be set to MSI (bridge to bridge.usb1.1 and 2 .

 

Some stuff has no drivers supported MSI mode.

 

I looked into the ms certified list and yes component are required to support it but from what I understand they re not required to enable it . I tried setting it my self .ROFL some driver supplied too many interrupt for say a 4 core I ended up with 8 interrupt .hopefully ms will supply the user with premade way to do 1msi per CPU core .I don't need to save power .lol .anyway ty for info .

 

Reread sober

 

Thanks mkb. When I set my gpu to msi it lowered my dpc from ~70-150 with a game running to 50-100.

 

so i did mine with no trouble at all...



they way i did it, is just copy the whole key from other branches