On Tue, Feb 8, 2022 at 10:45 PM Eric Blake <ebl...@redhat.com> wrote: > > On Sun, Jan 30, 2022 at 01:33:32AM +0200, Nir Soffer wrote: > > Make it easy to create a zeroed buffer via calloc(), preventing leaking > > sensitive info from the heap. > > > > Benchmarking show that creating a zeroed buffer is much slower compared > > shows
Will fix > > > with uninitialized buffer, but much faster compared with manually > > initializing the buffer with a loop. > > > > BenchmarkMakeAioBuffer-12 7252674 148.1 ns/op > > BenchmarkMakeAioBufferZero-12 262107 4181 ns/op > > BenchmarkAioBufferZero-12 17581 68759 ns/op > > > > It is interesting that creating a zeroed buffer is 3 times faster > > compared with making a new []byte slice: > > > > BenchmarkMakeAioBufferZero-12 247710 4440 ns/op > > BenchmarkMakeByteSlice-12 84117 13733 ns/op > > Some of this is due to how much vectorization the standard library > (whether libc or Go's core libraries) can do when bulk-zeroing > (zeroing 64 bits, or even a cache line at a time, in an unrolled loop, > is always going to be more performant than a naive loop of one byte at > a time). > > > > > Signed-off-by: Nir Soffer <nsof...@redhat.com> > > --- > > golang/aio_buffer.go | 6 ++++++ > > golang/libnbd_620_aio_buffer_test.go | 16 ++++++++++++++++ > > Another file that may fit better in the 0xx naming, especially if we > decide to duplicate similar functionality into the python or OCaml > bindings of being able to pre-generate a known-zero buffer for use in > passing to nbd_pread. > > As a helper API, this seems useful. But do we need any man page > documentation of a language-specific helper function? The AioBuffer type is documented here: https://pkg.go.dev/libguestfs.org/libnbd#AioBuffer Patch #3 golang: aio_buffer.go: Add missing documentation adds the missing documentation for the functions, We can add more documentation for the type. If we need task-based documentation I think improving libnbd-golang is the best way. _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
