Oracle 5.0 Reference Manual page 1448

MySQL Proxy FAQ
Yes, but it is not advised for now.
16.7.6.8: Is the system context switch expensive, how much overhead does the Lua script add?
Lua is fast and the overhead should be small enough for most applications. The raw packet overhead
is around 400 microseconds.
16.7.6.9: How much latency does a proxy add to a connection?
In the range of 400 microseconds per request.
16.7.6.10: Do you have to make one large script and call it at proxy startup, can I change scripts
without stopping and restarting (interrupting) the proxy?
You can just change the script and the proxy will reload it when a client connects.
16.7.6.11: If MySQL Proxy has to live on same machine as MySQL, are there any tuning
considerations to ensure both perform optimally?
MySQL Proxy can live on any box: application, database, or its own box. MySQL Proxy uses
comparatively little CPU or RAM, with negligible additional requirements or overhead.
16.7.6.12: I currently use SQL Relay for efficient connection pooling with a number of Apache
processes connecting to a MySQL server. Can MySQL Proxy currently accomplish this? My
goal is to minimize connection latency while keeping temporary tables available.
Yes.
16.7.6.13: Are these reserved function names (for example, error_result()) that get
automatically called?
Only functions and values starting with are provided by the proxy. All others are user
proxy.*
provided.
16.7.6.14: As the script is re-read by MySQL Proxy, does it cache this or is it looking at the file
system with each request?
It looks for the script at client-connect and reads it if it has changed, otherwise it uses the cached
version.
16.7.6.15: Given that there is a function, can a Lua script link up with
connect_server()
multiple servers?
MySQL Proxy provides some tutorials in the source package; one is
examples/tutorial-
keepalive.lua.
16.7.6.16: Is the MySQL Proxy an API?
No, MySQL Proxy is an application that forwards packets from a client to a server using the MySQL
network protocol. The MySQL Proxy provides a API allowing you to change its behavior.
16.7.6.17: The global namespace variable example with quotas does not persist after a reboot,
is that correct?
Yes. If you restart the proxy, you lose the results, unless you save them in a file.
16.7.6.18: Can MySQL Proxy handle SSL connections?
No, being the man-in-the-middle, Proxy cannot handle encrypted sessions because it cannot share the
SSL information.
16.7.6.19: Could MySQL Proxy be used to capture passwords?
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