X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=blobdiff_plain;f=backup%2Freadbuffer.c;fp=backup%2Freadbuffer.c;h=f389a77c3fce8bf6319bc4a2c6698dfe28e68dc9;hb=460e29f1c9232dafbdc161bf67d3e956d23eeb6b;hp=ec03c6a390a08022529e12d3727b287e3327718b;hpb=75b4ab2309a4391110249e2ce2f6611c71526b5b;p=chiark-utils.git

diff --git a/backup/readbuffer.c b/backup/readbuffer.c
index ec03c6a..f389a77 100644
--- a/backup/readbuffer.c
+++ b/backup/readbuffer.c
@@ -29,13 +29,18 @@
 
 #include <sys/time.h>
 #include <sys/types.h>
+#include <sys/mman.h>
 #include <assert.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <errno.h>
 #include <unistd.h>
 
-#define BUFFER 16*1024*1024
+#ifndef RWBUFFER_SIZE_MB
+#define RWBUFFER_SIZE_MB 16
+#endif
+
+#define BUFFER (RWBUFFER_SIZE_MB*1024*1024)
 #define WAITEMPTY ((BUFFER*1)/4)
 
 static inline int min(int a, int b) { return a<=b ? a : b; }