ghostty/src/benchmark/ at main · ptr.pet/ghostty · Tangled

ptr.pet / ghostty

0

This repository has no description

0

ghostty / src / benchmark /

at main 13 files

Mitchell Hashimoto benchmark: isolate parser hot loop from code-layout shifts 3mo ago

benchmark: isolate parser hot loop from code-layout shifts Extract the tight per-byte parsing loop from TerminalParser.step into a separate noinline function (parseAll). This eliminates a ~20% benchmark regression that appeared after the highway vendor changes despite zero changes to the parser source code. The root cause: the parser benchmark processes 50 MB of input through a byte-at-a-time DFA loop that is highly sensitive to instruction cache-line placement on Apple Silicon. The M-series cores fetch aligned 16-byte blocks; when the loop head lands near the end of a 64-byte cache line (offset 60), only one instruction fits in the first fetch versus four when aligned to offset 48. This causes ~29% more cycles for identical instruction counts. Previously the loop was inlined into the large step() function, so any code change anywhere in the binary (like the highway vendor restructuring) could shift the loop across a cache-line boundary. By making parseAll noinline, the loop gets its own function placement that is stable regardless of surrounding code changes.

3 months ago

benchmark: disable test on windows We don't appear to have a time source with enough resolution to get a non-zero duration on the benchmark test so it fails.

4 months ago

libghostty: export benchmark CLI API

1 year ago

CodepointWidth.zig

windows: avoid the use of wcwidth

5 months ago

GraphemeBreak.zig

Merge branch 'main' into grapheme-break

8 months ago

Remove unused imports

8 months ago

osc: remove inline from Parser.next

7 months ago

ScreenClone.zig

terminal: make stream processing infallible The terminal.Stream next/nextSlice functions can now no longer fail. All prior failure modes were fully isolated in the handler `vt` callbacks. As such, vt callbacks are now required to not return an error and handle their own errors somehow. Allowing streams to be fallible before was an incorrect design. It caused problematic scenarios like in `nextSlice` early terminating processing due to handler errors. This should not be possible. There is no safe way to bubble up vt errors through the stream because if nextSlice is called and multiple errors are returned, we can't coalesce them. We could modify that to return a partial result but its just more work for stream that is unnecessary. The handler can do all of this. This work was discovered due to cleanups to prepare for more C APIs. Less errors make C APIs easier to implement! And, it helps clean up our Zig, too.

5 months ago

TerminalParser.zig

benchmark: isolate parser hot loop from code-layout shifts Extract the tight per-byte parsing loop from TerminalParser.step into a separate noinline function (parseAll). This eliminates a ~20% benchmark regression that appeared after the highway vendor changes despite zero changes to the parser source code. The root cause: the parser benchmark processes 50 MB of input through a byte-at-a-time DFA loop that is highly sensitive to instruction cache-line placement on Apple Silicon. The M-series cores fetch aligned 16-byte blocks; when the loop head lands near the end of a 64-byte cache line (offset 60), only one instruction fits in the first fetch versus four when aligned to offset 48. This causes ~29% more cycles for identical instruction counts. Previously the loop was inlined into the large step() function, so any code change anywhere in the binary (like the highway vendor restructuring) could shift the loop across a cache-line boundary. By making parseAll noinline, the loop gets its own function placement that is stable regardless of surrounding code changes.

3 months ago

TerminalStream.zig

terminal: make stream processing infallible The terminal.Stream next/nextSlice functions can now no longer fail. All prior failure modes were fully isolated in the handler `vt` callbacks. As such, vt callbacks are now required to not return an error and handle their own errors somehow. Allowing streams to be fallible before was an incorrect design. It caused problematic scenarios like in `nextSlice` early terminating processing due to handler errors. This should not be possible. There is no safe way to bubble up vt errors through the stream because if nextSlice is called and multiple errors are returned, we can't coalesce them. We could modify that to return a partial result but its just more work for stream that is unnecessary. The handler can do all of this. This work was discovered due to cleanups to prepare for more C APIs. Less errors make C APIs easier to implement! And, it helps clean up our Zig, too.

5 months ago

benchmark: add option to microbenchmark OSC parser

8 months ago

benchmark: screen clone

8 months ago

Zig 0.15: zig build test

10 months ago