stream-clone: stop getting the file size of all file in v3
The point of v3 is to do less work in the locked section. It was currently not
the case.
This significantly boost performance. The following number comes from a large
private repository using perf::stream-locked-section:
base-line: 35.03 seconds
this-change: 24.50 seconds (-30%)
stream: in v3, skip the "size" fast path if the entries as some unknown size
We are about to prefetch size during the lock less in the v3 case. So we need to
avoid trying to use that prefetched size when it is not available.
See next changeset for the motivation.
perf-stream-locked-section: advertise the right version key in the help
As the v3 format is still experimental, its key is "v3-exp". The help text was
not pointing that out.
(we also fix `perf::stream-generate` in the process)
perf-stream-locked-section: fix the call to the v3 generator
That generator simply return chunks so we should not assign the return to a
tuple.
perf-stream-locked-section: actually use v1 generation when requested
We were fetching a v1 generator but actually using the v2 function…
Added signature for changeset
803e61387e86