Displaying 7 results from an estimated 7 matches for "d60086".
2020 Aug 07
2
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...w FDO inliner evaluates call site. It checks callee’s total sample count instead of callee’s entry count. This is less than ideal, but we couldn’t fix it due to profile quality issues – we can’t reliably get inlinee’s entry count with dwarf based approach, see discussion in https://reviews.llvm.org/D60086. That problem is solved with pseudo-probe, but until we change the inliner, we won’t see perf win from that particular profile quality improvement. There are other similar cases too, and that’s why we used profile quality metric instead of performance to assess pseudo-probe.
Some of the issues may...
2020 Aug 08
5
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...w FDO inliner evaluates call site. It checks callee’s total sample count instead of callee’s entry count. This is less than ideal, but we couldn’t fix it due to profile quality issues – we can’t reliably get inlinee’s entry count with dwarf based approach, see discussion in https://reviews.llvm.org/D60086<https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D60086&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=KfYo542rDdZQGClmgz-RBw&m=IiraiO5pLd86sJtoupX-V4fgITYAQHvv2GN-H_UmDXQ&s=TVgYwUBqNvzMAOEwn2FDgcKlvRrsbAvEXT4OscZS2n4&e=>. That problem is solved with pseudo-p...
2020 Aug 08
3
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...w FDO inliner evaluates call site. It checks callee’s total sample count instead of callee’s entry count. This is less than ideal, but we couldn’t fix it due to profile quality issues – we can’t reliably get inlinee’s entry count with dwarf based approach, see discussion in https://reviews.llvm.org/D60086<https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D60086&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=KfYo542rDdZQGClmgz-RBw&m=IiraiO5pLd86sJtoupX-V4fgITYAQHvv2GN-H_UmDXQ&s=TVgYwUBqNvzMAOEwn2FDgcKlvRrsbAvEXT4OscZS2n4&e=>. That problem is solved with pseudo-p...
2020 Aug 08
2
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...tes call site. It checks callee’s
> total sample count instead of callee’s entry count. This is less than
> ideal, but we couldn’t fix it due to profile quality issues – we can’t
> reliably get inlinee’s entry count with dwarf based approach, see
> discussion in https://reviews.llvm.org/D60086
> <https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D60086&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=KfYo542rDdZQGClmgz-RBw&m=IiraiO5pLd86sJtoupX-V4fgITYAQHvv2GN-H_UmDXQ&s=TVgYwUBqNvzMAOEwn2FDgcKlvRrsbAvEXT4OscZS2n4&e=>.
> That problem is solved wi...
2020 Aug 08
2
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...w FDO inliner evaluates call site. It checks callee’s total sample count instead of callee’s entry count. This is less than ideal, but we couldn’t fix it due to profile quality issues – we can’t reliably get inlinee’s entry count with dwarf based approach, see discussion in https://reviews.llvm.org/D60086<https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D60086&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=KfYo542rDdZQGClmgz-RBw&m=IiraiO5pLd86sJtoupX-V4fgITYAQHvv2GN-H_UmDXQ&s=TVgYwUBqNvzMAOEwn2FDgcKlvRrsbAvEXT4OscZS2n4&e=>. That problem is solved with pseudo-p...
2020 Aug 08
2
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
...w FDO inliner evaluates call site. It checks callee’s total sample count instead of callee’s entry count. This is less than ideal, but we couldn’t fix it due to profile quality issues – we can’t reliably get inlinee’s entry count with dwarf based approach, see discussion in https://reviews.llvm.org/D60086<https://urldefense.proofpoint.com/v2/url?u=https-3A__reviews.llvm.org_D60086&d=DwMFaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=KfYo542rDdZQGClmgz-RBw&m=IiraiO5pLd86sJtoupX-V4fgITYAQHvv2GN-H_UmDXQ&s=TVgYwUBqNvzMAOEwn2FDgcKlvRrsbAvEXT4OscZS2n4&e=>. That problem is solved with pseudo-p...
2020 Aug 07
4
[RFC] Context-sensitive Sample PGO with Pseudo-Instrumentation
Hi All,
Our team at Facebook is building a new context-sensitive Sample PGO as an alternative to the existing AutoFDO. We’d like to share our motivation, propose a new design, and reveal preliminary results on benchmarks. We will refer to the proposed design as CSSPGO in this RFC.
The new CSSPGO leverages simultaneous LBR and stack sampling to construct a full context-sensitive profile. It