Bug 350
Summary: | i386 context switch very slow compared to 2.4 due to wrmsr (performance) | ||
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Product: | Process Management | Reporter: | Andi Kleen (andi-bz) |
Component: | Scheduler | Assignee: | Robert Love (rlove) |
Status: | CLOSED CODE_FIX | ||
Severity: | normal | ||
Priority: | P2 | ||
Hardware: | i386 | ||
OS: | Linux | ||
Kernel Version: | 2.5.5x | Subsystem: | |
Regression: | --- | Bisected commit-id: | |
Attachments: | eliminate one wrmsr in i386 context switch |
Description
Andi Kleen
2003-02-11 17:06:55 UTC
Update: some patches and patch proposals for that exists now. First one of from me to fix the wrmsr for vm86 mode (attached) And some proposals from Linus/Jamie Lokier how to eliminate the wrmsr for the sysenter stack (no patch yet, just proposals) See surrounding thread also, including replies from Linus approving the idea: http://marc.theaimsgroup.com/?l=linux-kernel&m=104502360530576&w=2 (Jamie also has some ideas how to speed up ctx switch fast path more) Just someone needs to implement it.... Created attachment 140 [details]
eliminate one wrmsr in i386 context switch
Linus fixed it in 2.5.65. |