diff options
Diffstat (limited to 'DOCS/man/options.rst')
| -rw-r--r-- | DOCS/man/options.rst | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst index 8dcbe1bcd8..3ae3264969 100644 --- a/DOCS/man/options.rst +++ b/DOCS/man/options.rst @@ -4196,6 +4196,32 @@ Cache Currently, this is used for ``--cache-on-disk`` only. +``--stream-buffer-size=<bytesize>`` + Size of the low level stream byte buffer (default: 4KB). This is used as + buffer between demuxer and low level I/O (e.g. sockets). Generally, this + can be very small, and the main purpose is similar to the internal buffer + FILE in the C standard library will have. + + Half of the buffer is always used for guaranteed seek back, which is + important for unseekable input. + + There are known cases where this can help performance to set a large buffer: + + 1. mp4 files. libavformat may trigger many small seeks in both + directions, depending on how the file was muxed. + + 2. Certain network filesystems, which do not have a cache, and where + small reads can be inefficient. + + In other cases, setting this to a large value can reduce performance. + + Usually, read accesses are at half the buffer size, but it may happen that + accesses are done alternating with smaller and larger sizes (this is due to + the internal ring buffer wrap-around). + + See ``--list-options`` for defaults and value range. ``<bytesize>`` options + accept suffixes such as ``KiB`` and ``MiB``. + Network ------- |