From 614195777b3ee675d74d98953b086e0f8a4a494d Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Mon, 26 Feb 2024 15:33:39 -0500 Subject: [PATCH v3 4/5] Add pg_streaming_read_reset For rescan, we want to reuse the streaming read object and simply release the buffers that were pinned by the streaming read infrastructure. --- src/backend/storage/aio/streaming_read.c | 18 ++++++++++++++++++ src/include/storage/streaming_read.h | 1 + 2 files changed, 19 insertions(+) diff --git a/src/backend/storage/aio/streaming_read.c b/src/backend/storage/aio/streaming_read.c index 71f2c4a70b6..70f3ef051f8 100644 --- a/src/backend/storage/aio/streaming_read.c +++ b/src/backend/storage/aio/streaming_read.c @@ -610,3 +610,21 @@ pg_streaming_read_free(PgStreamingRead *pgsr) pfree(pgsr); } + + +/* + * Reset a streaming read object by releasing all of the buffers. Note that + * max_ios is not recalculated, so any changes to maintenance_io_concurrency and + * effective_io_concurrency will have no effect. + */ +void +pg_streaming_read_reset(PgStreamingRead *pgsr) +{ + Buffer buffer; + + /* Stop looking ahead, and unpin anything that wasn't consumed. */ + pgsr->finished = true; + while ((buffer = pg_streaming_read_buffer_get_next(pgsr, NULL)) != InvalidBuffer) + ReleaseBuffer(buffer); + pgsr->finished = false; +} diff --git a/src/include/storage/streaming_read.h b/src/include/storage/streaming_read.h index c4d3892bb26..63cef719e42 100644 --- a/src/include/storage/streaming_read.h +++ b/src/include/storage/streaming_read.h @@ -48,5 +48,6 @@ extern PgStreamingRead *pg_streaming_read_buffer_alloc(int flags, extern void pg_streaming_read_prefetch(PgStreamingRead *pgsr); extern Buffer pg_streaming_read_buffer_get_next(PgStreamingRead *pgsr, void **per_buffer_private); extern void pg_streaming_read_free(PgStreamingRead *pgsr); +extern void pg_streaming_read_reset(PgStreamingRead *pgsr); #endif -- 2.37.2