On Tue, 2011-12-27 at 10:21 +0900, 外川　康徳 wrote:

Hello folks,

Is there limit of "log_fifo_size" on syslog-ng output message quing?

I do know that real limit size of handling log messages depends on network environment or machine spec, but I'd like to know it has limit figure on its specification.

Nothing hard-coded in syslog-ng. It'll use memory once the queue fills up (e.g. it is not preallocated, memory is only used when actually being used). The internal representation of a log message can take about twice the log message size (could vary though), so if you know the average message size, you can get the maximum memory use for this purpose. Don't forget that queues are used for each destination, and although syslog-ng attempts to share memory for messages stored in various queues, it might happen that you actually store multiple copies. Hope this helps. -- Bazsi