Rent buffers used in SFTP reads #1738
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An SFTP download performs several reads from the server in parallel, allocating an array to store each result until it's ready to be consumed. Since these buffers are short-lived and normally of the same large-ish size (32KB), it seems like a good candidate for pooling.
Rob-Hague
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WojciechNagorski and
drieseng
as code owners
WojciechNagorski
approved these changes
Nov 18, 2025
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An SFTP download performs several reads from the server in parallel, allocating an array to store each result until it's ready to be consumed. Since these buffers are short-lived and normally of the same large-ish size (32KB), it seems like a good candidate for pooling.
In a test download, I see 3 or 4 such buffers allocated in the pool (~100KB), instead of e.g. 1MB or 8MB of arrays allocated (corresponding to the size of the file) at this layer.