Rename BufferAccessStrategyData.ring_size to nbuffers

The new name better reflects what the field is - the size of the buffers[]
array.  ring_size sounded more like it is in units of bytes.

An upcoming commit allows a BufferAccessStrategy of custom sizes, so it
seems relevant to improve this beforehand.

Author: Melanie Plageman
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/CAAKRu_YefVbhg4rAxU2frYFdTap61UftH-kUNQZBvAs%2BYK81Zg%40mail.gmail.com
This commit is contained in:
David Rowley 2023-04-03 23:31:16 +12:00
parent 4830f10243
commit 8d928e3a9f

View File

@ -74,7 +74,7 @@ typedef struct BufferAccessStrategyData
/* Overall strategy type */
BufferAccessStrategyType btype;
/* Number of elements in buffers[] array */
int ring_size;
int nbuffers;
/*
* Index of the "current" slot in the ring, ie, the one most recently
@ -541,7 +541,7 @@ BufferAccessStrategy
GetAccessStrategy(BufferAccessStrategyType btype)
{
BufferAccessStrategy strategy;
int ring_size;
int nbuffers;
/*
* Select ring size to use. See buffer/README for rationales.
@ -556,13 +556,13 @@ GetAccessStrategy(BufferAccessStrategyType btype)
return NULL;
case BAS_BULKREAD:
ring_size = 256 * 1024 / BLCKSZ;
nbuffers = 256 * 1024 / BLCKSZ;
break;
case BAS_BULKWRITE:
ring_size = 16 * 1024 * 1024 / BLCKSZ;
nbuffers = 16 * 1024 * 1024 / BLCKSZ;
break;
case BAS_VACUUM:
ring_size = 256 * 1024 / BLCKSZ;
nbuffers = 256 * 1024 / BLCKSZ;
break;
default:
@ -572,16 +572,16 @@ GetAccessStrategy(BufferAccessStrategyType btype)
}
/* Make sure ring isn't an undue fraction of shared buffers */
ring_size = Min(NBuffers / 8, ring_size);
nbuffers = Min(NBuffers / 8, nbuffers);
/* Allocate the object and initialize all elements to zeroes */
strategy = (BufferAccessStrategy)
palloc0(offsetof(BufferAccessStrategyData, buffers) +
ring_size * sizeof(Buffer));
nbuffers * sizeof(Buffer));
/* Set fields that don't start out zero */
strategy->btype = btype;
strategy->ring_size = ring_size;
strategy->nbuffers = nbuffers;
return strategy;
}
@ -615,7 +615,7 @@ GetBufferFromRing(BufferAccessStrategy strategy, uint32 *buf_state)
/* Advance to next ring slot */
if (++strategy->current >= strategy->ring_size)
if (++strategy->current >= strategy->nbuffers)
strategy->current = 0;
/*