Core: added cyclic memory buffer support for error_log. Example of usage: error_log memory:16m debug; This allows to configure debug logging with minimum impact on performance. It's especially useful when rare crashes are experienced under high load. The log can be extracted from a coredump using the following gdb script: set $log = ngx_cycle->log while $log->writer != ngx_log_memory_writer set $log = $log->next end set $buf = (ngx_log_memory_buf_t *) $log->wdata dump binary memory debug_log.txt $buf->start $buf->end