Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitc8d9d87

Browse files
author
Daniel Shelepanov
committed
intermediate wraparound
1 parent9aca915 commitc8d9d87

File tree

4 files changed

+39
-9
lines changed

4 files changed

+39
-9
lines changed

‎engine.c

Lines changed: 23 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -353,6 +353,10 @@ ptrackCheckpoint(void)
353353
structstatstat_buf;
354354
uint64i=0;
355355
uint64j=0;
356+
XLogRecPtrnew_init_lsn;
357+
uint32new_init_lsn32;
358+
uint32latest_lsn;
359+
boollsn_was_advanced= false;
356360

357361
elog(DEBUG1,"ptrack checkpoint");
358362

@@ -408,21 +412,25 @@ ptrackCheckpoint(void)
408412
ptrack_write_chunk(ptrack_tmp_fd,&crc, (char*)ptrack_map,
409413
offsetof(PtrackMapHdr,init_lsn));
410414

415+
latest_lsn=pg_atomic_read_u32(&ptrack_map->latest_lsn);
411416
init_lsn=pg_atomic_read_u32(&ptrack_map->init_lsn);
412417

413418
/* Set init_lsn during checkpoint if it is not set yet */
414419
if (init_lsn==InvalidXLogRecPtr)
415420
{
416-
XLogRecPtrnew_init_lsn;
417-
uint32new_init_lsn32;
418-
419421
if (RecoveryInProgress())
420422
new_init_lsn=GetXLogReplayRecPtr(NULL);
421423
else
422424
new_init_lsn=GetXLogInsertRecPtr();
423425

424426
new_init_lsn32= (uint32)(new_init_lsn >>16);
425-
427+
pg_atomic_write_u32(&ptrack_map->init_lsn,new_init_lsn32);
428+
init_lsn=new_init_lsn32;
429+
}
430+
elseif (lsn_diff(lsn_advance(init_lsn,PtrackLSNGap),latest_lsn)<0)
431+
{
432+
new_init_lsn32=lsn_advance(init_lsn,PtrackLSNGap);
433+
lsn_was_advanced= true;
426434
pg_atomic_write_u32(&ptrack_map->init_lsn,new_init_lsn32);
427435
init_lsn=new_init_lsn32;
428436
}
@@ -449,7 +457,11 @@ ptrackCheckpoint(void)
449457
* TODO: is it safe and can we do any better?
450458
*/
451459
lsn=pg_atomic_read_u32(&ptrack_map->entries[i]);
452-
buf[j].value=lsn;
460+
461+
if (lsn_was_advanced&&lsn_diff(lsn,init_lsn)<0)
462+
buf[j].value=InvalidXLogRecPtr;
463+
else
464+
buf[j].value=lsn;
453465

454466
i++;
455467
j++;
@@ -467,7 +479,6 @@ ptrackCheckpoint(void)
467479
ptrack_write_chunk(ptrack_tmp_fd,&crc, (char*)buf,writesz);
468480
elog(DEBUG5,"ptrack checkpoint: i "UINT64_FORMAT", j "UINT64_FORMAT", writesz %zu PtrackContentNblocks "UINT64_FORMAT,
469481
i,j,writesz, (uint64)PtrackContentNblocks);
470-
471482
j=0;
472483
}
473484
}
@@ -726,7 +737,12 @@ ptrack_mark_block(RelFileNodeBackend smgr_rnode,
726737
!pg_atomic_compare_exchange_u32(&ptrack_map->init_lsn, (uint32*)&old_init_lsn.value,new_lsn32));
727738
}
728739

729-
/* Atomically assign new LSN value to the first slot */
740+
/* Assign latest_lsn first */
741+
old_lsn.value=pg_atomic_read_u32(&ptrack_map->latest_lsn);
742+
while (old_lsn.value<new_lsn32&&
743+
!pg_atomic_compare_exchange_u32(&ptrack_map->latest_lsn, (uint32*)&old_lsn.value,new_lsn32));
744+
745+
/* Then, atomically assign new LSN value to the first slot */
730746
old_lsn.value=pg_atomic_read_u32(&ptrack_map->entries[slot1]);
731747
elog(DEBUG3,"ptrack_mark_block: map[%zu]=%u <- %u",slot1,old_lsn.value,new_lsn32);
732748
while (old_lsn.value<new_lsn32&&

‎engine.h

Lines changed: 3 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -65,6 +65,8 @@ typedef struct PtrackMapHdr
6565
*/
6666
uint32version_num;
6767

68+
/* LSN of current writing position */
69+
pg_atomic_uint32latest_lsn;
6870
/* LSN of the moment, when map was last enabled. */
6971
pg_atomic_uint32init_lsn;
7072

@@ -94,6 +96,7 @@ typedef PtrackMapHdr * PtrackMap;
9496
#defineBID_HASH_FUNC(bid) \
9597
(DatumGetUInt64(hash_any_extended((unsigned char *)&bid, sizeof(bid), 0)))
9698

99+
#definePtrackLSNGap10e8
97100
/*
98101
* Per process pointer to shared ptrack_map
99102
*/

‎ptrack.c

Lines changed: 11 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -533,6 +533,8 @@ ptrack_get_pagemapset(PG_FUNCTION_ARGS)
533533
datapagemap_tpagemap;
534534
int64pagecount=0;
535535
chargather_path[MAXPGPATH];
536+
uint32init_lsn=InvalidXLogRecPtr;
537+
boolwithin_ptrack_map= true;
536538

537539
/* Exit immediately if there is no map */
538540
if (ptrack_map==NULL)
@@ -639,6 +641,7 @@ ptrack_get_pagemapset(PG_FUNCTION_ARGS)
639641
SRF_RETURN_DONE(funcctx);
640642
}
641643

644+
init_lsn=pg_atomic_read_u32(&ptrack_map->init_lsn);
642645
hash=BID_HASH_FUNC(ctx->bid);
643646
slot1= (size_t)(hash %PtrackContentNblocks);
644647

@@ -649,8 +652,11 @@ ptrack_get_pagemapset(PG_FUNCTION_ARGS)
649652
(uint16) (update_lsn1 >>16), (uint16)update_lsn1,
650653
ctx->bid.blocknum,ctx->relpath);
651654

655+
if (init_lsn!=InvalidXLogRecPtr)
656+
within_ptrack_map=lsn_diff(init_lsn,update_lsn1) <=0;
657+
652658
/* Only probe the second slot if the first one is marked */
653-
if (update_lsn1 >=ctx->lsn)
659+
if (within_ptrack_map&&lsn_diff(ctx->lsn,update_lsn1) <=0)
654660
{
655661
slot2= (size_t)(((hash <<32) | (hash >>32)) %PtrackContentNblocks);
656662
update_lsn2=pg_atomic_read_u32(&ptrack_map->entries[slot2]);
@@ -660,8 +666,11 @@ ptrack_get_pagemapset(PG_FUNCTION_ARGS)
660666
(uint16) (update_lsn1 >>16), (uint16)update_lsn2,
661667
ctx->bid.blocknum,ctx->relpath);
662668

669+
if (init_lsn!=InvalidXLogRecPtr)
670+
within_ptrack_map=lsn_diff(init_lsn,update_lsn2) <=0;
671+
663672
/* Block has been changed since specified LSN. Mark it in the bitmap */
664-
if (update_lsn2 >=ctx->lsn)
673+
if (within_ptrack_map&&lsn_diff(ctx->lsn,update_lsn2) <=0)
665674
{
666675
pagecount+=1;
667676
datapagemap_add(&pagemap,ctx->bid.blocknum % ((BlockNumber)RELSEG_SIZE));

‎ptrack.h

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -47,6 +47,8 @@
4747
#definenodeOf(ndbck)(ndbck).node
4848
#endif
4949

50+
#definelsn_diff(lsn1,lsn2)((int32)(lsn1-lsn2))
51+
#definelsn_advance(lsn,incr)((uint32)(lsn+incr))
5052
/*
5153
* Structure identifying block on the disk.
5254
*/

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp