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[Bug 1175] New - swap readahead sets the page referenced bit



http://distro.conectiva.com.br/bugzilla/show_bug.cgi?id=1175

--- shadow/1175	Wed Jan 31 16:54:08 2001
+++ shadow/1175.tmp.4930	Wed Jan 31 16:54:08 2001
@@ -0,0 +1,27 @@
++============================================================================+
+| swap readahead sets the page referenced bit                                |
++----------------------------------------------------------------------------+
+|        Bug #: 1175                        Product: Linux kernel MM         |
+|       Status: NEW                         Version: 2.4 (stable)            |
+|   Resolution:                            Platform:                         |
+|     Severity: normal                   OS/Version:                         |
+|     Priority: P2                        Component: linux mm                |
++----------------------------------------------------------------------------+
+|  Assigned To: linux-mm-bugs@nl.linux.org                                   |
+|  Reported By: marcelo@conectiva.com.br                                     |
+|      CC list: Cc:                                                          |
++----------------------------------------------------------------------------+
+|          URL:                                                              |
++============================================================================+
+|                              DESCRIPTION                                   |
+The swapin readahead code uses the function read_swap_cache_async()"
+for each page it wants to readahead.
+
+Now this function (read_swap_cache_async()) uses __find_page_nolock, which moves
+the page to the active list, or sets the referenced bit on the page (this will
+end up aging the page up later).
+
+Pages which are being readahead should be left "old", so in case they are not
+used by any process, they get freed before other (probably more useful) pages.
+
+This can be easily fixed using Rik's __find_page_simple().
\ No newline at end of file

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