@@ -347,6 +347,10 @@ GenericXLogFinish(GenericXLogState *state)
347347
348348START_CRIT_SECTION ();
349349
350+ /*
351+ * Compute deltas if necessary, write changes to buffers, mark
352+ * buffers dirty, and register changes.
353+ */
350354for (i = 0 ;i < MAX_GENERIC_XLOG_PAGES ;i ++ )
351355{
352356PageData * pageData = & state -> pages [i ];
@@ -359,41 +363,34 @@ GenericXLogFinish(GenericXLogState *state)
359363page = BufferGetPage (pageData -> buffer );
360364pageHeader = (PageHeader )pageData -> image ;
361365
366+ /*
367+ * Compute delta while we still have both the unmodified page and
368+ * the new image. Not needed if we are logging the full image.
369+ */
370+ if (!(pageData -> flags & GENERIC_XLOG_FULL_IMAGE ))
371+ computeDelta (pageData ,page , (Page )pageData -> image );
372+
373+ /*
374+ * Apply the image, being careful to zero the "hole" between
375+ * pd_lower and pd_upper in order to avoid divergence between
376+ * actual page state and what replay would produce.
377+ */
378+ memcpy (page ,pageData -> image ,pageHeader -> pd_lower );
379+ memset (page + pageHeader -> pd_lower ,0 ,
380+ pageHeader -> pd_upper - pageHeader -> pd_lower );
381+ memcpy (page + pageHeader -> pd_upper ,
382+ pageData -> image + pageHeader -> pd_upper ,
383+ BLCKSZ - pageHeader -> pd_upper );
384+
385+ MarkBufferDirty (pageData -> buffer );
386+
362387if (pageData -> flags & GENERIC_XLOG_FULL_IMAGE )
363388{
364- /*
365- * A full-page image does not require us to supply any xlog
366- * data. Just apply the image, being careful to zero the
367- * "hole" between pd_lower and pd_upper in order to avoid
368- * divergence between actual page state and what replay would
369- * produce.
370- */
371- memcpy (page ,pageData -> image ,pageHeader -> pd_lower );
372- memset (page + pageHeader -> pd_lower ,0 ,
373- pageHeader -> pd_upper - pageHeader -> pd_lower );
374- memcpy (page + pageHeader -> pd_upper ,
375- pageData -> image + pageHeader -> pd_upper ,
376- BLCKSZ - pageHeader -> pd_upper );
377-
378389XLogRegisterBuffer (i ,pageData -> buffer ,
379390REGBUF_FORCE_IMAGE |REGBUF_STANDARD );
380391}
381392else
382393{
383- /*
384- * In normal mode, calculate delta and write it as xlog data
385- * associated with this page.
386- */
387- computeDelta (pageData ,page , (Page )pageData -> image );
388-
389- /* Apply the image, with zeroed "hole" as above */
390- memcpy (page ,pageData -> image ,pageHeader -> pd_lower );
391- memset (page + pageHeader -> pd_lower ,0 ,
392- pageHeader -> pd_upper - pageHeader -> pd_lower );
393- memcpy (page + pageHeader -> pd_upper ,
394- pageData -> image + pageHeader -> pd_upper ,
395- BLCKSZ - pageHeader -> pd_upper );
396-
397394XLogRegisterBuffer (i ,pageData -> buffer ,REGBUF_STANDARD );
398395XLogRegisterBufData (i ,pageData -> delta ,pageData -> deltaLen );
399396}
@@ -402,15 +399,14 @@ GenericXLogFinish(GenericXLogState *state)
402399/* Insert xlog record */
403400lsn = XLogInsert (RM_GENERIC_ID ,0 );
404401
405- /* Set LSNand mark buffers dirty */
402+ /* Set LSN */
406403for (i = 0 ;i < MAX_GENERIC_XLOG_PAGES ;i ++ )
407404{
408405PageData * pageData = & state -> pages [i ];
409406
410407if (BufferIsInvalid (pageData -> buffer ))
411408continue ;
412409PageSetLSN (BufferGetPage (pageData -> buffer ),lsn );
413- MarkBufferDirty (pageData -> buffer );
414410}
415411END_CRIT_SECTION ();
416412}