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

diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c
index c690d5f15f21a6bc93a534c3ee33a5efff707525..f122709fbe2b43169a2d33d1f84bbe7f0b75560b 100644 (file)
--- a/src/backend/storage/buffer/freelist.c
+++ b/src/backend/storage/buffer/freelist.c
@@ -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;
 
        /*