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The "Performance" page has been changed by RandallLeeds. The comment on this change is: Add information on +A <n> flag. http://wiki.apache.org/couchdb/Performance?action=diff&rev1=5&rev2=6 -------------------------------------------------- If your system does not use PAM, a {{{ulimit}}} command is usually available for use in a custom script to launch CouchDB with increased resource limits. If necessary, feel free to increase this limits as long as your hardware can handle the load. + = Disk and File System Performance = + Using faster disks, striped RAID arrays and modern file systems can all speed up your CouchDB deployment. However, there is one option that can increase the responsiveness of your CouchDB server when disk performance is a bottleneck. From the erlang documentation for the file module: {{{ + On operating systems with thread support, it is possible to let file operations be performed in threads of their own, allowing other Erlang processes to continue executing in parallel with the file operations. See the command line flag +A in erl(1).}}} + Setting this argument to a number greater than zero can keep your CouchDB installation responsive even during periods of heavy disk utilization. The easiest way to set this option is through the {{{ERL_FLAGS}}} environment variable. For example, to give Erlang four threads with which to perform i/o operations add the following to {{{(prefix)/etc/defaults/couchdb}}} (or equivalent): {{{ + export ERL_FLAGS="+A 4"}}} +
