From 6e693b42dcb0b332364b0414107826826925c49f Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Thu, 18 Dec 2014 14:21:55 +0100 Subject: [PATCH] journal: optimize iteration by skipping exhausted files If from a previous iteration we know we are at the end of a journal file, don't bother looking into the file again. This is complicated by the fact that the EOF does not have to be permanent (think of "journalctl -f"). So we also check if the number of entries in the journal file changed. This optimization has a similar effect as "journal: optimize iteration: skip whole files behind current location" had. --- src/journal/journal-file.h | 1 + src/journal/sd-journal.c | 8 +++++++- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/src/journal/journal-file.h b/src/journal/journal-file.h index 808417619..561982fe3 100644 --- a/src/journal/journal-file.h +++ b/src/journal/journal-file.h @@ -78,6 +78,7 @@ typedef struct JournalFile { direction_t last_direction; LocationType location_type; + uint64_t last_n_entries; char *path; struct stat last_stat; diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c index f3aae9b0e..0aaf2257d 100644 --- a/src/journal/sd-journal.c +++ b/src/journal/sd-journal.c @@ -729,12 +729,18 @@ static int next_with_matches( static int next_beyond_location(sd_journal *j, JournalFile *f, direction_t direction) { Object *c; - uint64_t cp; + uint64_t cp, n_entries; int r; assert(j); assert(f); + /* If we hit EOF before, recheck if any new entries arrived. */ + n_entries = le64toh(f->header->n_entries); + if (f->location_type == LOCATION_TAIL && n_entries == f->last_n_entries) + return 0; + f->last_n_entries = n_entries; + if (f->last_direction == direction && f->current_offset > 0) { cp = f->current_offset; -- 2.30.2