diff options
| author | Alan Jenkins <alan-jenkins@tuffmail.co.uk> | 2009-05-21 22:22:37 +0200 |
|---|---|---|
| committer | Kay Sievers <kay.sievers@vrfy.org> | 2009-05-21 22:22:37 +0200 |
| commit | f503f6b22fa54d1a65156a51d8b3311190c73ae5 (patch) | |
| tree | 5003144371ce463fe5ba2387b9777cd8cddd24ad /udev/lib/libudev.h | |
| parent | f9b3f88f71f5bdfb18aa4bfba00d72fa41fdf286 (diff) | |
udevd: implement a more efficient queue file format
Directory lookups show up in profiling. The queue files are responsible
for a large proportion of file-related system calls in udev coldplug.
Instead of creating a file for each event, append their details to a
log file. The file is periodically rebuilt (garbage-collected) to
prevent it from growing indefinitely.
This single queue file replaces both the queue directory and the
uevent_seqnum file. On desktop systems the file tends not to grow
beyond one page. So it should also save a small amount of memory in
tmpfs.
Tests on a running EeePC indicate average savings of 5% *udevd* cpu time
as measured by oprofile. __link_path_walk is reduced from 1.5% to
1.3%. It is not completely clear where the rest of the gains come from.
In tests running ~400 events, the queue file is rebuilt about 5 times.
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Diffstat (limited to 'udev/lib/libudev.h')
| -rw-r--r-- | udev/lib/libudev.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/udev/lib/libudev.h b/udev/lib/libudev.h index 9346eb4ddd..9b51ea3300 100644 --- a/udev/lib/libudev.h +++ b/udev/lib/libudev.h @@ -115,6 +115,8 @@ unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue) int udev_queue_get_udev_is_active(struct udev_queue *udev_queue); int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue); int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum); +int udev_queue_get_seqnum_sequence_is_finished(struct udev_queue *udev_queue, + unsigned long long int start, unsigned long long int end); struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue); struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev_queue); #endif |