diff options
Diffstat (limited to 'drivers/md/bcache/alloc.c')
| -rw-r--r-- | drivers/md/bcache/alloc.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index a0cc1bc6d884..6cc6c0f9c3a9 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -525,15 +525,21 @@ struct open_bucket { /* * We keep multiple buckets open for writes, and try to segregate different - * write streams for better cache utilization: first we look for a bucket where - * the last write to it was sequential with the current write, and failing that - * we look for a bucket that was last used by the same task. + * write streams for better cache utilization: first we try to segregate flash + * only volume write streams from cached devices, secondly we look for a bucket + * where the last write to it was sequential with the current write, and + * failing that we look for a bucket that was last used by the same task. * * The ideas is if you've got multiple tasks pulling data into the cache at the * same time, you'll get better cache utilization if you try to segregate their * data and preserve locality. * - * For example, say you've starting Firefox at the same time you're copying a + * For example, dirty sectors of flash only volume is not reclaimable, if their + * dirty sectors mixed with dirty sectors of cached device, such buckets will + * be marked as dirty and won't be reclaimed, though the dirty data of cached + * device have been written back to backend device. + * + * And say you've starting Firefox at the same time you're copying a * bunch of files. Firefox will likely end up being fairly hot and stay in the * cache awhile, but the data you copied might not be; if you wrote all that * data to the same buckets it'd get invalidated at the same time. @@ -550,7 +556,10 @@ static struct open_bucket *pick_data_bucket(struct cache_set *c, struct open_bucket *ret, *ret_task = NULL; list_for_each_entry_reverse(ret, &c->data_buckets, list) - if (!bkey_cmp(&ret->key, search)) + if (UUID_FLASH_ONLY(&c->uuids[KEY_INODE(&ret->key)]) != + UUID_FLASH_ONLY(&c->uuids[KEY_INODE(search)])) + continue; + else if (!bkey_cmp(&ret->key, search)) goto found; else if (ret->last_write_point == write_point) ret_task = ret; |