нашел у фпм такое
; Log limit on number of characters in the single line (log entry). If the
; line is over the limit, it is wrapped on multiple lines. The limit is for
; all logged characters including message prefix and suffix if present. However
; the new line character does not count into it as it is present only when
; logging to a file descriptor. It means the new line character is not present
; when logging to syslog.
; Default Value: 1024
;log_limit = 4096
применил а все равно получаю 1024 буфер фулл