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Post Ax61mVtlO4Sa9RCPMO by [email protected] |
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More posts by [email protected] |
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Post #Ax5pxrJgtdSYJWyChc by [email protected] |
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0 likes, 1 repeats |
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The kernel may run slower.(help text for MITIGATION_RETHUNK)When I look at my b… |
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Post #Ax5saM4TCSfmbsKoEq by [email protected] |
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I think I even know why. The unconditional jump is fully handled by the BPU, wh… |
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Post #Ax61mVUwsKbuuTaagK by [email protected] |
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@ptesarik I'm afraid not. Decoding of which instructions? If the lone '… |
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Post #Ax61mVbgTHzxFMjyBE by [email protected] |
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@amonakov Interesting. Indeed, on a second thought, my explanation doesn't … |
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Post #Ax61mVtlO4Sa9RCPMO by [email protected] |
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@amonakov But are you 100% certain that BPU cannot predict never-before-seen un… |
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Post #Ax637CNnF0GDeyflpo by [email protected] |
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@ptesarik have you checked how much of the microbenchmark runs out of the DSB? … |
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Post #Ax637CTStunVwZKIfw by [email protected] |
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@amonakov ALL_IDQ_UOPS = 198633974709%UOPS.DSB = 62.3%%UOPS.MITE = 27.6%%UOPS.M… |
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Post #Ax63PlCEXluyqR7I7E by [email protected] |
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@amonakov Oh, and yes, I do see a lot of hits in its_return_thunk:Samples │ … |
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Post #Ax63w7y7Pc9SjqwrFw by [email protected] |
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@ptesarik no, not 100% at all. Branch prediction needs to work in several stage… |
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Post #Ax63w83R5qPB0LR6Xo by [email protected] |
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@amonakov FWIW Intel documentation says:Branches that do not have a history in … |
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Post #Ax64NY2qZM2nQoEde4 by [email protected] |
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@ptesarik ah, this its_return_thunk is new, it doesn't desync the return ad… |
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Post #Ax64NY8WEGa5iOtAUC by [email protected] |
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@amonakov Oh, right, I thought I made it clear that this is a jmp to a ret, not… |
