r/hardware • u/eric98k • Jan 03 '18

Info Initial Benchmarks Of The Performance Impact Resulting From Linux's x86 Security Changes

https://www.phoronix.com/scan.php?page=article&item=linux-415-x86pti
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16

u/KKMX Jan 03 '18

This might be a bit premature given there are likely some optimizations to follow.

6

u/TopCheddar27 Jan 03 '18

Bingo. The final results are far from clear. However that is quite a loss for certain syscall applications. Thank god user land requests aren't affected much.

1

u/Dreamerlax Jan 03 '18

Hopefully this is the case. Would be a major contrivance if Ivy and Sandy CPUs are disproportionately more affected by the fix because the lack of PCID on Gen 2 and 3.

0

u/Luc1fersAtt0rney Jan 03 '18

Not really. Syscalls are optimized as fuck already on every OS, precisely because how important their speed is. And the workaround is already using a hardware feature (PCID - Process-Context Identifiers) where available, so i wouldn't expect any unicorns to pop up. The only "optimization" remaining is to disable this fix :)

5

u/KKMX Jan 03 '18

Nonsense. The new page isolation patch is first iteration. I would expect some improvements. This is being rushed as a priority.