I've attached a patch with a few typo fixes and what looks like an
incorrect type for max_ios. It's an int16 and I think it needs to be
an int. Doing "max_ios = Min(max_ios, PG_INT16_MAX);" doesn't do
anything when max_ios is int16.
David
diff --git a/src/backend/storage/aio/read_stream.c
b/src/backend/storage/aio/read_stream.c
index 634cf4f0d1..74b9bae631 100644
--- a/src/backend/storage/aio/read_stream.c
+++ b/src/backend/storage/aio/read_stream.c
@@ -26,12 +26,12 @@
*
* B) I/O is necessary, but fadvise is undesirable because the access is
* sequential, or impossible because direct I/O is enabled or the system
- * doesn't support advice. There is no benefit in looking ahead more than
- * io_combine_limit, because in this case only goal is larger read system
+ * doesn't support fadvise. There is no benefit in looking ahead more than
+ * io_combine_limit, because in this case the only goal is larger read system
* calls. Looking further ahead would pin many buffers and perform
* speculative work looking ahead for no benefit.
*
- * C) I/O is necesssary, it appears random, and this system supports fadvise.
+ * C) I/O is necessary, it appears random, and this system supports fadvise.
* We'll look further ahead in order to reach the configured level of I/O
* concurrency.
*
@@ -418,7 +418,7 @@ read_stream_begin_relation(int flags,
ReadStream *stream;
size_t size;
int16 queue_size;
- int16 max_ios;
+ int max_ios;
int strategy_pin_limit;
uint32 max_pinned_buffers;
Oid tablespace_id;
@@ -447,6 +447,8 @@ read_stream_begin_relation(int flags,
max_ios =
get_tablespace_maintenance_io_concurrency(tablespace_id);
else
max_ios = get_tablespace_io_concurrency(tablespace_id);
+
+ /* Cap to INT16_MAX to avoid overflowing below */
max_ios = Min(max_ios, PG_INT16_MAX);
/*
