Use an array buffer for the sftp packet stream #1649
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The sftp packet stream runs within but independently of the channel data stream, meaning a channel data packet can contain multiple sftp packets, or an sftp packet can be split across multiple channel data packets. Normally the packets are sized such there is a 1-to-1 relationship for efficiency. When this doesn't happen the library falls back to buffering via a List<byte>, which is not so efficient. This change uses an array-based buffer instead. In a sample download which hit this fallback I see about a 20% reduction in memory allocated.
WojciechNagorski
approved these changes
Jun 6, 2025
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The sftp packet stream runs within but independently of the channel data stream, meaning a channel data packet can contain multiple sftp packets, or an sftp packet can be split across multiple channel data packets.
Normally the packets are sized such there is a 1-to-1 relationship for efficiency. When this doesn't happen the library falls back to buffering via a List<byte>, which is not so efficient. This change uses an array-based buffer instead.
In a sample download which hit this fallback I see about a 20% reduction in memory allocated.