From a96d2712f349629d7fe2186e2620f1704cbdee50 Mon Sep 17 00:00:00 2001 From: Godmar Back Date: Sat, 4 Nov 2006 20:08:27 +0000 Subject: [PATCH] clarify use of timer_sleep or acceptable alternatives for implementing write-behind cache flushing. --- doc/filesys.texi | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/doc/filesys.texi b/doc/filesys.texi index 744c0b2..9075c9a 100644 --- a/doc/filesys.texi +++ b/doc/filesys.texi @@ -311,11 +311,8 @@ blocks back to disk. The cache should also be written back to disk in @func{filesys_done}, so that halting Pintos flushes the cache. If you have @func{timer_sleep} from the first project working, write-behind is -an excellent application. If you're still using the base -implementation of @func{timer_sleep}, be aware that it busy-waits, which -is not acceptable here (or elsewhere). If @func{timer_sleep}'s delays seem too -short or too long, reread the explanation of the @option{-r} option to -@command{pintos} (@pxref{Debugging versus Testing}). +an excellent application. Otherwise, you may implement a less general +facility, but make sure that it does not exhibit busy-waiting. You should also implement @dfn{read-ahead}, that is, automatically fetch the next block of a file -- 2.30.2