SESES Speculative Execution Pass Lands In LLVM With "Extreme Performance Implications"

[phoronix]

Phoronix: SESES Speculative Execution Pass Lands In LLVM With "Extreme Performance Implications"

The Google-backed SESES pass for LLVM to help fend off speculative execution vulnerabilities has been merged for LLVM 11, but in opting to enable this patch you lose much of your system's performance...

http://www.phoronix.com/scan.php?page=news_item&px=LLVM-SESES-Merged

[ms178]

Could someone explain to me why any sane person would want to enable this pass, wanting to pay the price for this instead of buying new hardware? Not only is it just horrible from a performance perspective but also from a performance per energy standpoint which means the TCO goes through the roof. An investment into new hardware would pay for itself for better use of the energy involved.

[pyler]

Waster manpower. Nobody will use it.

[elatllat]

Lol is 7% about the speed of some A53's (rpi3,etc) the fastest non speculative cores.

[cl333r]

Could someone explain to me why any sane person would want to enable this pass, wanting to pay the price for this instead of buying new hardware?

Hw vendors would love this patch to stay as is forever and people to buy new hw as you said.

[V1tol]

Lol is 7% about the speed of some A53's (rpi3,etc) the fastest non speculative cores.

Actually A53 is also speculative (any CPU that has branch predictor is), it just don't suffer from Spectre and Meltdown.

[CommunityMember]

Could someone explain to me why any sane person would want to enable this pass

For "crypto critical" routines, ensuring that your keystuff is not accidentally exposed may be a huge win. Not all of (for example) OpenSSL is crypto-critical, but some parts are, and if certain routines are appropriately isolated by compiler flags, those routines could be robustified for a number of potential vulnerabilities (publicly, and non-publicly) known.

[muncrief]

Yikes! Why? This doesn't make any sense.

If you're worried about security then move to a processor that's secure. There's no way that a new system could cost more than losing 93% of your processing power.

[CochainComplex]

Yikes! Why? This doesn't make any sense.

If you're worried about security then move to a processor that's secure. There's no way that a new system could cost more than losing 93% of your processing power.

Intel: *hold my Beer*

[Guest]

Could someone explain to me why any sane person would want to enable this pass, wanting to pay the price for this instead of buying new hardware? Not only is it just horrible from a performance perspective but also from a performance per energy standpoint which means the TCO goes through the roof. An investment into new hardware would pay for itself for better use of the energy involved.

It's for paranoid people. Most likely nuclear launch code protection and copyrighted content protection.