database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-10-31 10:30:33 +03:00
Code Activity

Port single-page btree vacuum logic to hash indexes.

Browse Source 
This is advantageous for hash indexes for the same reasons it's good
for btrees: it accelerates space recycling, reducing bloat.

Ashutosh Sharma, reviewed by Amit Kapila and by me.  A bit of
additional hacking by me.

Discussion: http://postgr.es/m/CAE9k0PkRSyzx8dOnokEpUi2A-RFZK72WN0h9DEMv_ut9q6bPRw@mail.gmail.com
This commit is contained in:
Robert Haas
2017-03-15 22:18:56 -04:00
parent 2038bf41c9
commit 6977b8b7f4
10 changed files with 517 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
src/include/access/hash.h
View File

@@ -57,6 +57,7 @@ typedef uint32 Bucket;
#define LH_BUCKET_BEING_POPULATED (1 << 4)
#define LH_BUCKET_BEING_SPLIT (1 << 5)
#define LH_BUCKET_NEEDS_SPLIT_CLEANUP (1 << 6)
#define LH_PAGE_HAS_DEAD_TUPLES (1 << 7)
#define LH_PAGE_TYPE \
(LH_OVERFLOW_PAGE|LH_BUCKET_PAGE|LH_BITMAP_PAGE|LH_META_PAGE)
@@ -86,6 +87,7 @@ typedef HashPageOpaqueData *HashPageOpaque;
#define H_NEEDS_SPLIT_CLEANUP(opaque) ((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP)
#define H_BUCKET_BEING_SPLIT(opaque) ((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT)
#define H_BUCKET_BEING_POPULATED(opaque) ((opaque)->hasho_flag & LH_BUCKET_BEING_POPULATED)
#define H_HAS_DEAD_TUPLES(opaque) ((opaque)->hasho_flag & LH_PAGE_HAS_DEAD_TUPLES)
/*
* The page ID is for the convenience of pg_filedump and similar utilities,
@@ -95,6 +97,13 @@ typedef HashPageOpaqueData *HashPageOpaque;
*/
#define HASHO_PAGE_ID 0xFF80
typedef struct HashScanPosItem /* what we remember about each match */
{
ItemPointerData heapTid; /* TID of referenced heap item */
OffsetNumber indexOffset; /* index item's location within page */
} HashScanPosItem;
/*
* HashScanOpaqueData is private state for a hash index scan.
*/
@@ -135,6 +144,9 @@ typedef struct HashScanOpaqueData
* referred only when hashso_buc_populated is true.
*/
bool hashso_buc_split;
/* info about killed items if any (killedItems is NULL if never used) */
HashScanPosItem *killedItems; /* tids and offset numbers of killed items */
int numKilled; /* number of currently stored items */
} HashScanOpaqueData;
typedef HashScanOpaqueData *HashScanOpaque;
@@ -300,7 +312,7 @@ extern Datum hash_uint32(uint32 k);
/* private routines */
/* hashinsert.c */
extern void _hash_doinsert(Relation rel, IndexTuple itup);
extern void _hash_doinsert(Relation rel, IndexTuple itup, Relation heapRel);
extern OffsetNumber _hash_pgaddtup(Relation rel, Buffer buf,
Size itemsize, IndexTuple itup);
extern void _hash_pgaddmultitup(Relation rel, Buffer buf, IndexTuple *itups,
@@ -361,7 +373,7 @@ extern HSpool *_h_spoolinit(Relation heap, Relation index, uint32 num_buckets);
extern void _h_spooldestroy(HSpool *hspool);
extern void _h_spool(HSpool *hspool, ItemPointer self,
Datum *values, bool *isnull);
extern void _h_indexbuild(HSpool *hspool);
extern void _h_indexbuild(HSpool *hspool, Relation heapRel);
/* hashutil.c */
extern bool _hash_checkqual(IndexScanDesc scan, IndexTuple itup);
@@ -381,6 +393,7 @@ extern BlockNumber _hash_get_oldblock_from_newbucket(Relation rel, Bucket new_bu
extern BlockNumber _hash_get_newblock_from_oldbucket(Relation rel, Bucket old_bucket);
extern Bucket _hash_get_newbucket_from_oldbucket(Relation rel, Bucket old_bucket,
uint32 lowmask, uint32 maxbucket);
extern void _hash_kill_items(IndexScanDesc scan);
/* hash.c */
extern void hashbucketcleanup(Relation rel, Bucket cur_bucket,