Subject: Re: [libssh2] How to increase performance of libssh2 SFTP Read/Write

Re: [libssh2] How to increase performance of libssh2 SFTP Read/Write

From: Mononen Jussi <>
Date: Mon, 18 Jun 2007 13:28:26 +0300

>> * src/packet.c 1.39 - reading bigger blocks from
>> network. Significantly improves performance due to lesser syscalls
>> (and probably it influences the TCP window changes too). This is a
>> temporary measure while libssh2 is mostly synchronous.
>> I made diff of vers 1.38 and 1.39 of packet.c to see what
>> specific changes are made for the above performance
>> workaround and made the same changes to packet.c of
>> libssh2-0.14 release.
>> But still there was no performance boost up as such while
>> reading the file from remote SFTP server.

I have also changed the LIBSSH2_CHANNEL_WINDOW_DEFAULT to 128kb.

How much data you request with one call to libssh2_sftp_read -function?
You should read at least 32kb, ie. the max packet size.


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Received on 2007-06-18