Tuning Subversion over HTTP
Use HTTP keep-alive
A simple svn cat https://... can generate something like 278 packets going over the wire. This may be due to a sub-optimal configuration of the Apache web server. If the network traffic contains a lot of SYN/SYN Ack packets then a simple tweak in the Apache config file can give a big gain in performance: The KeepAlive option tells Apache to allow a connection open after the requested page has been server. That way a client can request a new page without going through the TCP handshaking process. A sensible configuration might look like:
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
# KeepAliveTimeout: Number of seconds to wait for the next request from the
# same client on the same connection.
With this simple trick I could drop the number of packets from 278 to 100.
If path-based authorisation is not needed, then the "SVNPathAuthz off" config option helped to drop further packets.
More tuning tips
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