diff -ur linux-2.2.18/fs/proc/array.c linux/fs/proc/array.c
--- linux-2.2.18/fs/proc/array.c	Wed Dec 13 11:43:28 2000
+++ linux/fs/proc/array.c	Tue Feb 27 11:52:52 2001
@@ -274,6 +274,8 @@
 		"disk_wio %u %u %u %u\n"
 		"disk_rblk %u %u %u %u\n"
 		"disk_wblk %u %u %u %u\n"
+		"read %u %u\n"	/* added by FvH: needed for sar-statistics */
+		"write %u %u\n"	/* read/write n nbytes */
 		"page %u %u\n"
 #ifdef CONFIG_ARCH_S390
                 "swap %u %u\n"
@@ -290,6 +292,8 @@
 		"disk_wio %u %u %u %u\n"
 		"disk_rblk %u %u %u %u\n"
 		"disk_wblk %u %u %u %u\n"
+		"read %u %u\n"	/* added by FvH: needed for sar-statistics */
+		"write %u %u\n"	/* read/write n nbytes */
 		"page %u %u\n"
 #ifdef CONFIG_ARCH_S390           
                 "swap %u %u\n"
@@ -313,6 +317,8 @@
 		kstat.dk_drive_rblk[2], kstat.dk_drive_rblk[3],
 		kstat.dk_drive_wblk[0], kstat.dk_drive_wblk[1],
 		kstat.dk_drive_wblk[2], kstat.dk_drive_wblk[3],
+		kstat.n_reads, kstat.n_reads_cnt,
+		kstat.n_writes, kstat.n_writes_cnt,
 		kstat.pgpgin,
 		kstat.pgpgout,
 		kstat.pswpin,
diff -ur linux-2.2.18/fs/read_write.c linux/fs/read_write.c
--- linux-2.2.18/fs/read_write.c	Mon Sep  4 19:39:27 2000
+++ linux/fs/read_write.c	Tue Feb 27 11:49:27 2001
@@ -2,6 +2,11 @@
  *  linux/fs/read_write.c
  *
  *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  Additions by FvH: read[v]/write[v] now keep track
+ *  of the number of reads/writes and the number of bytes
+ *  read or written. Needed to be able to do some thorough
+ *  analysis.
  */
 
 #include <linux/malloc.h> 
@@ -10,6 +15,7 @@
 #include <linux/file.h>
 #include <linux/uio.h>
 #include <linux/smp_lock.h>
+#include <linux/kernel_stat.h>
 
 #include <asm/uaccess.h>
 
@@ -121,6 +127,9 @@
 
 	lock_kernel();
 
+	kstat.n_reads++;	/* for sar statistics */
+	kstat.n_reads_cnt += count;
+
 	ret = -EBADF;
 	file = fget(fd);
 	if (!file)
@@ -151,6 +160,9 @@
 
 	lock_kernel();
 
+	kstat.n_writes++;	/* for sar statistics */
+	kstat.n_writes_cnt += count;
+
 	ret = -EBADF;
 	file = fget(fd);
 	if (!file)
@@ -230,6 +242,17 @@
 				 ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE),
 				inode, file, file->f_pos, tot_len);
 	if (ret) goto out;
+
+	if (type == VERIFY_READ)
+	{
+		kstat.n_reads++;	/* for sar statistics */
+		kstat.n_reads_cnt += tot_len;
+	}
+	else
+	{
+		kstat.n_writes++;	/* for sar statistics */
+		kstat.n_writes_cnt += tot_len;
+	}
 
 	/*
 	 * Then do the actual IO.  Note that sockets need to be handled
diff -ur linux-2.2.18/include/linux/kernel_stat.h linux/include/linux/kernel_stat.h
--- linux-2.2.18/include/linux/kernel_stat.h	Wed Dec 13 12:03:16 2000
+++ linux/include/linux/kernel_stat.h	Tue Feb 27 11:46:09 2001
@@ -32,6 +32,8 @@
 	unsigned int ierrors, oerrors;
 	unsigned int collisions;
 	unsigned int context_swtch;
+	unsigned int n_reads, n_writes;
+	unsigned int n_reads_cnt, n_writes_cnt;
 };
 
 extern struct kernel_stat kstat;