[erlang-questions] couchdb performace 10x: using NIF for file io

Martin Scholl <>
Mon Oct 25 14:56:01 CEST 2010


On 10/25/2010 06:21 AM, Max Lapshin wrote:
> There is other interesting question: are there plans to support
> asynchronous disk IO? It is already somehow implemented in FreeBSD and
> in progress in Linux.
For linux-land I have written a NIF for it (using a thread for
collecting the results via io_getevents/2).
The performance difference isn't huge compared with blocking I/O -- but
unlike blocking I/O you have to worry about alignment (I/O as well as
memory) and other issues much more.

For Linux-land I'd recommend to stick with Linus' recommendation:
	http://kerneltrap.org/node/7563



Martin


More information about the erlang-questions mailing list