* [PATCH v2] fs: improve ramfs_truncate speed
@ 2018-09-26 11:08 Marcin Niestroj
0 siblings, 0 replies; only message in thread
From: Marcin Niestroj @ 2018-09-26 11:08 UTC (permalink / raw)
To: barebox; +Cc: Maciej Zagrabski, Marcin Niestroj
During sequential writes into single file, fs layer is consequently
calling ramfs_truncate() function. When file size grows
ramfs_truncate() takes more and more time to complete, due to
interations through all already written data chunks. As an example
loading ~450M image using usb fastboot protocol took over 500s to
complete.
Use ramfs_find_chunk() function to search for last chunk of data in
ramfs_truncate() implementation, which saves a lot of loop
iterations. As a result loading ~450M image using usb fastboot
protocol takes around 25s now.
Tested-by: Maciej Zagrabski <m.zagrabski@grinn-global.com>
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
---
Changes v1 -> v2 (suggested by Sascha):
* use positive logic, i.e. 'if (data)'
* rebase patch on top of "fs: ramfs: make chunk counting in
truncate() better readable"
fs/ramfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/ramfs.c b/fs/ramfs.c
index 8ba8d77de..e3f83bca3 100644
--- a/fs/ramfs.c
+++ b/fs/ramfs.c
@@ -379,7 +379,9 @@ static int ramfs_truncate(struct device_d *dev, FILE *f, ulong size)
}
if (newchunks > oldchunks) {
- if (!data) {
+ if (data) {
+ data = ramfs_find_chunk(node, oldchunks);
+ } else {
node->data = ramfs_get_chunk();
if (!node->data)
return -ENOMEM;
--
2.19.0
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2018-09-26 11:09 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-09-26 11:08 [PATCH v2] fs: improve ramfs_truncate speed Marcin Niestroj
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox