dm kcopyd: reserve fewer pages

Reserve just the minimum of pages needed to process one job.

Because we allocate pages from page allocator, we don't need to reserve
a large number of pages.  The maximum job size is SUB_JOB_SIZE and we
calculate the number of reserved pages based on this.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mikulas Patocka 2011-05-29 13:03:11 +01:00 committed by Alasdair G Kergon
parent bda8efec5c
commit 5f43ba2950
4 changed files with 6 additions and 13 deletions

View File

@ -30,6 +30,7 @@
#define SUB_JOB_SIZE 128
#define SPLIT_COUNT 8
#define MIN_JOBS 8
#define RESERVE_PAGES (DIV_ROUND_UP(SUB_JOB_SIZE << SECTOR_SHIFT, PAGE_SIZE))
/*-----------------------------------------------------------------
* Each kcopyd client has its own little pool of preallocated
@ -636,8 +637,7 @@ int kcopyd_cancel(struct kcopyd_job *job, int block)
/*-----------------------------------------------------------------
* Client setup
*---------------------------------------------------------------*/
int dm_kcopyd_client_create(unsigned min_pages,
struct dm_kcopyd_client **result)
int dm_kcopyd_client_create(struct dm_kcopyd_client **result)
{
int r = -ENOMEM;
struct dm_kcopyd_client *kc;
@ -663,7 +663,7 @@ int dm_kcopyd_client_create(unsigned min_pages,
kc->pages = NULL;
kc->nr_reserved_pages = kc->nr_free_pages = 0;
r = client_reserve_pages(kc, min_pages);
r = client_reserve_pages(kc, RESERVE_PAGES);
if (r)
goto bad_client_pages;

View File

@ -22,7 +22,6 @@
#define DM_MSG_PREFIX "raid1"
#define MAX_RECOVERY 1 /* Maximum number of regions recovered in parallel. */
#define DM_KCOPYD_PAGES 64
#define DM_RAID1_HANDLE_ERRORS 0x01
#define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS)
@ -1116,7 +1115,7 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto err_destroy_wq;
}
r = dm_kcopyd_client_create(DM_KCOPYD_PAGES, &ms->kcopyd_client);
r = dm_kcopyd_client_create(&ms->kcopyd_client);
if (r)
goto err_destroy_wq;

View File

@ -39,11 +39,6 @@ static const char dm_snapshot_merge_target_name[] = "snapshot-merge";
*/
#define SNAPSHOT_COPY_PRIORITY 2
/*
* Reserve 1MB for each snapshot initially (with minimum of 1 page).
*/
#define SNAPSHOT_PAGES (((1UL << 20) >> PAGE_SHIFT) ? : 1)
/*
* The size of the mempool used to track chunks in use.
*/
@ -1116,7 +1111,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto bad_hash_tables;
}
r = dm_kcopyd_client_create(SNAPSHOT_PAGES, &s->kcopyd_client);
r = dm_kcopyd_client_create(&s->kcopyd_client);
if (r) {
ti->error = "Could not create kcopyd client";
goto bad_kcopyd;

View File

@ -25,8 +25,7 @@
* To use kcopyd you must first create a dm_kcopyd_client object.
*/
struct dm_kcopyd_client;
int dm_kcopyd_client_create(unsigned num_pages,
struct dm_kcopyd_client **result);
int dm_kcopyd_client_create(struct dm_kcopyd_client **result);
void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);
/*