Fix incorrect buffer allocation which resulted in cache misses wasting a page of the cache each access, causing bad I/O performance (long standing bug). Speedup noticeable in decode operations.

1 files changed, 4 insertions, 6 deletions

diff --git a/xdelta3/xdelta3-blkcache.h b/xdelta3/xdelta3-blkcache.h
index d4ae926..2102a58 100644
--- a/xdelta3/xdelta3-blkcache.h
+++ b/xdelta3/xdelta3-blkcache.h
@@ -309,9 +309,13 @@ main_getblk_lru (xd3_source *source, xoff_t blkno,
               main_blklru_list_remove (blru);
               main_blklru_list_push_back (& lru_list, blru);
               (*blrup) = blru;
+              IF_DEBUG1 (DP(RINT "[getblk_lru] HIT blkno = %"Z"u lru_size=%d\n",
+                    blkno, lru_size));
               return 0;
             }
         }
+      IF_DEBUG1 (DP(RINT "[getblk_lru] MISS blkno = %"Z"u lru_size=%d\n",
+                    blkno, lru_size));
     }
 
   if (do_src_fifo)
@@ -512,12 +516,6 @@ main_getblk_func (xd3_stream *stream,
 
   XD3_ASSERT (sfile->source_position == pos);
 
-  if (did_seek &&
-      (ret = main_getblk_lru (source, blkno, & blru, & is_new)))
-    {
-      return ret;
-    }
-
   if ((ret = main_read_primary_input (sfile,
                                       (uint8_t*) blru->blk,
                                       source->blksize,