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Updated default value of hnsw.scan_mem_multiplier [skip ci]

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Lines changed: 3 additions & 3 deletions

Original file line number	Diff line number	Diff line change
`@@ -505,10 +505,10 @@ SET hnsw.max_scan_tuples = 20000;`
`505`	`505`
`506`	`506`	`Note: This is approximate and does not apply to the initial scan`
`507`	`507`
`508`		-When increasing this, you may also need to increase the max amount of memory an iterative scan can use, which is a multiple of`work_mem` (2 by default)
	`508`	+When increasing this, you may also need to increase the max amount of memory an iterative scan can use, which is a multiple of`work_mem` (1 by default)
`509`	`509`
`510`	`510`	```sql
`511`		`-SEThnsw.scan_mem_multiplier=4;`
	`511`	`+SEThnsw.scan_mem_multiplier=2;`
`512`	`512`	```
`513`	`513`
`514`	`514`	`You can see when this is needed by enabling debug messages`
`@@ -520,7 +520,7 @@ SET client_min_messages = debug1;`
`520`	`520`	`which will show when a scan reaches the memory limit`
`521`	`521`
`522`	`522`	```text
`523`		`-DEBUG: hnsw index scan reached memory limit after40000 tuples`
	`523`	`+DEBUG: hnsw index scan reached memory limit after20000 tuples`
`524`	`524`	`HINT: Increase hnsw.scan_mem_multiplier to scan more tuples.`
`525`	`525`	```
`526`	`526`

Lines changed: 1 addition & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -91,7 +91,7 @@ HnswInit(void)`
`91`	`91`	`/* Same range and default as hash_mem_multiplier */`
`92`	`92`	`DefineCustomRealVariable("hnsw.scan_mem_multiplier","Sets the multiple of work_mem to use for iterative scans",`
`93`	`93`	`NULL,&hnsw_scan_mem_multiplier,`
`94`		`-2,1,1000,PGC_USERSET,0,NULL,NULL,NULL);`
	`94`	`+1,1,1000,PGC_USERSET,0,NULL,NULL,NULL);`
`95`	`95`
`96`	`96`	`MarkGUCPrefixReserved("hnsw");`
`97`	`97`	`}`

Lines changed: 1 addition & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -185,7 +185,7 @@ ERROR: 0 is outside the valid range for parameter "hnsw.max_scan_tuples" (1 ..`
`185`	`185`	`SHOW hnsw.scan_mem_multiplier;`
`186`	`186`	`hnsw.scan_mem_multiplier`
`187`	`187`	`--------------------------`
`188`		`-2`
	`188`	`+1`
`189`	`189`	`(1 row)`
`190`	`190`
`191`	`191`	`SET hnsw.scan_mem_multiplier = 0;`

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