Added read log caching and fixed a possible bug in write cacheing. (4d5d1ae2) · Commits · Software / OSDI20 Artifacts / mariadb

Docs/manual.texi

+4 −0

Original line number	Diff line number	Diff line
		@@ -46851,6 +46851,10 @@ Fixed bug when joining with caching (unlikely to happen).
		Fixed race condition when using the binary log and @code{INSERT DELAYED}
		which could cause the binary log to have rows that was not yet written
		to MyISAM tables.
		@item
		Changed caching of binary log to make replication slightly faster.
		@item
		Fixed bug in replication on Mac OS X.
		@end itemize

		@node News-3.23.45, News-3.23.44, News-3.23.46, News-3.23.x

+21 −6

Original line number	Diff line number	Diff line
		@@ -32,20 +32,35 @@

		void my_b_seek(IO_CACHE *info,my_off_t pos)
		{
		my_off_t offset = (pos - info->pos_in_file);
		DBUG_ENTER("my_b_seek");
		DBUG_PRINT("enter",("pos: %lu", (ulong) pos));

		if (info->type == READ_CACHE)
		{
		if ((ulonglong) offset < (ulonglong) (info->rc_end - info->buffer))
		{
		/* The read is in the current buffer; Reuse it */
		info->rc_pos = info->buffer + offset;
		DBUG_VOID_RETURN;
		}
		else
		{
		/* Force a new read on next my_b_read */
		info->rc_pos=info->rc_end=info->buffer;
		}
		}
		else if (info->type == WRITE_CACHE)
		{
		byte* try_rc_pos;
		try_rc_pos = info->rc_pos + (pos - info->pos_in_file);
		if (try_rc_pos >= info->buffer && try_rc_pos <= info->rc_end)
		/* If write is in current buffer, reuse it */
		if ((ulonglong) offset <
		(ulonglong) (info->rc_end - info->buffer))
		{
		info->rc_pos = try_rc_pos;
		return;
		info->rc_pos = info->buffer + offset;
		DBUG_VOID_RETURN;
		}
		flush_io_cache(info);
		info->rc_end=(info->buffer+info->buffer_length-(pos & (IO_SIZE-1)));
		}
		info->pos_in_file=pos;
		info->seek_not_done=1;