bufmgr: Remove buffer-write-dirty tracepoints

The trace point was using the relfileno / fork / block for the to-be-read-in
buffer. Some upcoming work would make that more expensive to provide. We still
have buffer-flush-start/done, which can serve most tracing needs that
buffer-write-dirty could serve.

Discussion: https://postgr.es/m/f5164e7a-eef6-8972-75a3-8ac622ed0c6e@iki.fi

Author: anarazel

doc/src/sgml/monitoring.sgml

@@ -7817,23 +7817,6 @@ FROM pg_stat_get_backend_idset() AS backendid;
       it's typically not actually been written to disk yet.)
       The arguments are the same as for <literal>buffer-flush-start</literal>.</entry>
     </row>
-    <row>
-     <entry><literal>buffer-write-dirty-start</literal></entry>
-     <entry><literal>(ForkNumber, BlockNumber, Oid, Oid, Oid)</literal></entry>
-     <entry>Probe that fires when a server process begins to write a dirty
-      buffer.  (If this happens often, it implies that
-      <xref linkend="guc-shared-buffers"/> is too
-      small or the background writer control parameters need adjustment.)
-      arg0 and arg1 contain the fork and block numbers of the page.
-      arg2, arg3, and arg4 contain the tablespace, database, and relation OIDs
-      identifying the relation.</entry>
-    </row>
-    <row>
-     <entry><literal>buffer-write-dirty-done</literal></entry>
-     <entry><literal>(ForkNumber, BlockNumber, Oid, Oid, Oid)</literal></entry>
-     <entry>Probe that fires when a dirty-buffer write is complete.
-      The arguments are the same as for <literal>buffer-write-dirty-start</literal>.</entry>
-    </row>
     <row>
      <entry><literal>wal-buffer-write-dirty-start</literal></entry>
      <entry><literal>()</literal></entry>

src/backend/storage/buffer/bufmgr.c

@@ -1280,21 +1280,11 @@ BufferAlloc(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 				}
 
 				/* OK, do the I/O */
-				TRACE_POSTGRESQL_BUFFER_WRITE_DIRTY_START(forkNum, blockNum,
-														  smgr->smgr_rlocator.locator.spcOid,
-														  smgr->smgr_rlocator.locator.dbOid,
-														  smgr->smgr_rlocator.locator.relNumber);
-
 				FlushBuffer(buf, NULL, IOOBJECT_RELATION, io_context);
 				LWLockRelease(BufferDescriptorGetContentLock(buf));
 
 				ScheduleBufferTagForWriteback(&BackendWritebackContext,
 											  &buf->tag);
-
-				TRACE_POSTGRESQL_BUFFER_WRITE_DIRTY_DONE(forkNum, blockNum,
-														 smgr->smgr_rlocator.locator.spcOid,
-														 smgr->smgr_rlocator.locator.dbOid,
-														 smgr->smgr_rlocator.locator.relNumber);
 			}
 			else
 			{

src/backend/utils/probes.d

@@ -66,8 +66,6 @@ provider postgresql {
 	probe buffer__sync__start(int, int);
 	probe buffer__sync__written(int);
 	probe buffer__sync__done(int, int, int);
-	probe buffer__write__dirty__start(ForkNumber, BlockNumber, Oid, Oid, Oid);
-	probe buffer__write__dirty__done(ForkNumber, BlockNumber, Oid, Oid, Oid);
 
 	probe deadlock__found();