Hi,
I've made a new version of IO statistics in kstat that remove the
previous limitations of MAX_MAJOR
I've made tests on my machine.
Could someone test it, please?
Feedback welcome.
Bye
-jec
--- /tmp/linux-2.4.18-vanilla/include/linux/kernel_stat.h Thu Nov 22 20:46:19 2001
+++ /toc/linux-2.4.18-reempt/include/linux/kernel_stat.h Wed Mar 6 18:02:57 2002
@@ -12,18 +12,37 @@
* used by rstatd/perfmeter
*/
-#define DK_MAX_MAJOR 16
-#define DK_MAX_DISK 16
+#define DK_MAX_DEVICES 64
+#define DK_BUCKETS 256
+
+
+struct _kstat_block_io
+{
+ struct _kstat_block_io* next;
+
+
unsigned int major;
+ unsigned int minor;
+
+
unsigned int io;
+ unsigned int rio;
+ unsigned int wio;
+ unsigned int rblk;
+ unsigned int wblk;
+};
+typedef struct _kstat_block_io kstat_block_io;
+
+
+/* static array of IO stats */
+extern unsigned int kstat_devices_current_index;
+extern kstat_block_io kstat_devices_array[DK_MAX_DEVICES];
+
+
struct kernel_stat {
unsigned int per_cpu_user[NR_CPUS],
per_cpu_nice[NR_CPUS],
per_cpu_system[NR_CPUS];
-
unsigned int dk_drive[DK_MAX_MAJOR][DK_MAX_DISK];
-
unsigned int dk_drive_rio[DK_MAX_MAJOR][DK_MAX_DISK];
-
unsigned int dk_drive_wio[DK_MAX_MAJOR][DK_MAX_DISK];
-
unsigned int dk_drive_rblk[DK_MAX_MAJOR][DK_MAX_DISK];
-
unsigned int dk_drive_wblk[DK_MAX_MAJOR][DK_MAX_DISK];
+ kstat_block_io* io_stat_tbl[DK_BUCKETS];
unsigned int pgpgin, pgpgout;
unsigned int pswpin, pswpout;
#if !defined(CONFIG_ARCH_S390)
@@ -37,6 +56,103 @@
extern struct kernel_stat kstat;
+
+
+/* Size of the table */
+extern const unsigned int kstat_block_io_tbl_size;
+
+/* hash function */
+static inline unsigned kstat_block_io_hash(unsigned int major, unsigned
int minor)
+{
+ return major * 1999 ^ minor;
+}
+
+
+/* add an IO stat */
+static inline kstat_block_io* kstat_block_io_add(unsigned int major,
unsigned int minor)
+{
+ unsigned int i;
+
kstat_block_io* p;
+ kstat_block_io* pstat;
+
+
if (kstat_devices_current_index >= DK_MAX_DEVICES)
+
{
+
printk("ERROR: kstat: No more slot for device IO stats. Try
extending DK_MAX_DEVICES\n");
+
return 0;
+
}
+
+ pstat = &kstat_devices_array[kstat_devices_current_index];
+
kstat_devices_current_index++;
+ pstat->next = 0;
+ pstat->major = major;
+ pstat->minor = minor;
+ pstat->io = 0;
+ pstat->rio = 0;
+ pstat->wio = 0;
+ pstat->rblk = 0;
+ pstat->wblk = 0;
+
+ i = kstat_block_io_hash(major, minor) % kstat_block_io_tbl_size;
+ p = kstat.io_stat_tbl[i];
+
if (p == 0)
+
{
+
kstat.io_stat_tbl[i] = pstat;
+
}
+
else
+
{
+
printk("WARNING: kstat: Collision found in IO stat accounting table
(add). Try extending DK_BUCKETS\n");
+ while (p->next != 0)
+
{
+ p = p->next;
+
}
+
p->next = pstat;
+
}
+
return pstat;
+}
+
+/* lookup an IO stat */
+static inline kstat_block_io* kstat_block_io_lookup(unsigned major,
unsigned minor)
+{
+
unsigned int i = kstat_block_io_hash(major, minor) %
kstat_block_io_tbl_size;
+
kstat_block_io* p = kstat.io_stat_tbl[i];
+
while (p && p->major != major && p->minor != minor)
+
{
+
printk("WARNING: kstat: Collision found in IO stat accounting table
(lookup). Try extending DK_BUCKETS\n");
+
p = p->next;
+
}
+
if (p == 0)
+
{
+
p = kstat_block_io_add(major, minor);
+
if (p == 0)
+
{
+
return 0;
+
}
+
}
+
return p;
+}
+
+/* This is used by MD to see if IDLE */
+static inline unsigned long kstat_get_rwblk(unsigned int major,
unsigned int minor)
+{
+ kstat_block_io* stat = kstat_block_io_lookup(major, minor);
+ if (stat == 0)
+
{
+
printk("ERROR: kstat: No IO stat found for (%d/%d)\n", major, minor);
+ return 0;
+
}
+ return stat->rblk + stat->wblk;
+}
+
+
+
+
+
+
+
+
+
+
+
#if !defined(CONFIG_ARCH_S390)
/*
* Number of interrupts per specific IRQ source, since bootup
--- /tmp/linux-2.4.18-vanilla/drivers/md/md.c Mon Feb 25 20:37:58 2002
+++ /toc/linux-2.4.18-reempt/drivers/md/md.c Wed Mar 6 16:46:56 2002
@@ -3284,6 +3284,9 @@
return NULL;
}
+/* MD devices are major=9 and minor=1-31 */
+#define DK_MAX_MAJOR 16
+#define DK_MAX_DISK 32
static unsigned int sync_io[DK_MAX_MAJOR][DK_MAX_DISK];
void md_sync_acct(kdev_t dev, unsigned long nr_sectors)
{
@@ -3305,15 +3308,12 @@
unsigned long curr_events;
idle = 1;
-
ITERATE_RDEV(mddev,rdev,tmp) {
+
ITERATE_RDEV(mddev,rdev,tmp)
+
{
int major = MAJOR(rdev->dev);
int idx = disk_index(rdev->dev);
-
if ((idx >= DK_MAX_DISK) || (major >= DK_MAX_MAJOR))
-
continue;
-
-
curr_events = kstat.dk_drive_rblk[major][idx] +
-
kstat.dk_drive_wblk[major][idx] ;
+ curr_events = kstat_get_rwblk(major, idx);
curr_events -= sync_io[major][idx];
if ((curr_events - rdev->last_events) > 32) {
rdev->last_events = curr_events;
--- /tmp/linux-2.4.18-vanilla/drivers/block/ll_rw_blk.c Mon Feb 25 20:37:57 2002
+++ /toc/linux-2.4.18-reempt/drivers/block/ll_rw_blk.c Wed Mar 6 18:12:03 2002
@@ -501,19 +501,22 @@
unsigned long nr_sectors, int new_io)
{
unsigned int major = MAJOR(dev);
-
unsigned int index;
+
unsigned int minor = MINOR(dev);
+ kstat_block_io* stat = kstat_block_io_lookup(major, minor);
-
index = disk_index(dev);
-
if ((index >= DK_MAX_DISK) || (major >= DK_MAX_MAJOR))
-
return;
+ if (stat == 0)
+ {
+
printk("ERROR: kstat: Haven't found an IO stat struct for major=%d
/ minor=%d\n", major, minor);
+ return;
+
}
-
kstat.dk_drive[major][index] += new_io;
+
stat->io += new_io;
if (rw == READ) {
-
kstat.dk_drive_rio[major][index] += new_io;
-
kstat.dk_drive_rblk[major][index] += nr_sectors;
+
stat->rio += new_io;
+
stat->rblk += nr_sectors;
} else if (rw == WRITE) {
-
kstat.dk_drive_wio[major][index] += new_io;
-
kstat.dk_drive_wblk[major][index] += nr_sectors;
+
stat->wio += new_io;
+
stat->wblk += nr_sectors;
} else
printk(KERN_ERR "drive_stat_acct: cmd not R/W?\n");
}
--- /tmp/linux-2.4.18-vanilla/fs/proc/proc_misc.c Wed Nov 21 06:29:09 2001
+++ /toc/linux-2.4.18-reempt/fs/proc/proc_misc.c Wed Mar 6 17:41:28 2002
@@ -282,25 +282,19 @@
len += sprintf(page + len, " %u", kstat_irqs(i));
#endif
-
len += sprintf(page + len, "\ndisk_io: ");
+ len += sprintf(page + len, "\ndisk_io: ");
-
for (major = 0; major < DK_MAX_MAJOR; major++) {
-
for (disk = 0; disk < DK_MAX_DISK; disk++) {
-
int active = kstat.dk_drive[major][disk] +
-
kstat.dk_drive_rblk[major][disk] +
-
kstat.dk_drive_wblk[major][disk];
-
if (active)
-
len += sprintf(page + len,
-
"(%u,%u):(%u,%u,%u,%u,%u) ",
-
major, disk,
-
kstat.dk_drive[major][disk],
-
kstat.dk_drive_rio[major][disk],
-
kstat.dk_drive_rblk[major][disk],
-
kstat.dk_drive_wio[major][disk],
-
kstat.dk_drive_wblk[major][disk]
-
);
-
}
-
}
+ for (i = 0; i < kstat_devices_current_index; i++)
+ {
+ kstat_block_io* stat = &kstat_devices_array[i];
+ len += sprintf( page + len, "(%u,%u):(%u,%u,%u,%u,%u) ",
+ stat->major, stat->minor,
+ stat->io,
+ stat->rio,
+ stat->wio,
+ stat->rblk,
+ stat->wblk );
+ }
len += sprintf(page + len,
"\nctxt %u\n"
On Wed, Mar 06, 2002 at 06:16:55PM +0100, Jean-Eric Cuendet wrote:
> I've made a new version of IO statistics in kstat that remove the
> previous limitations of MAX_MAJOR
> I've made tests on my machine.
> Could someone test it, please?
> Feedback welcome.
Your mailer was hungry and ate the patch (small examples):
> +
> +
> unsigned int major;
> + unsigned int minor;
> +
> +
> unsigned int io;
> + unsigned int rio;
> + unsigned int wio;
...
> +
> if (p == 0)
> +
> {
> +
> kstat.io_stat_tbl[i] = pstat;
> +
> }
> +
--
Russell King ([email protected]) The developer of ARM Linux
http://www.arm.linux.org.uk/personal/aboutme.html
On Wed, Mar 06, 2002 at 06:16:55PM +0100, Jean-Eric Cuendet wrote:
[...]
> len += sprintf(page + len,
> -
> "(%u,%u):(%u,%u,%u,%u,%u) ",
> -
> major, disk,
> -
> kstat.dk_drive[major][disk],
> -
> kstat.dk_drive_rio[major][disk],
> -
> kstat.dk_drive_rblk[major][disk],
> -
> kstat.dk_drive_wio[major][disk],
> -
> kstat.dk_drive_wblk[major][disk]
> -
> );
> -
> }
> -
> }
> + for (i = 0; i < kstat_devices_current_index; i++)
> + {
> + kstat_block_io* stat = &kstat_devices_array[i];
> + len += sprintf( page + len, "(%u,%u):(%u,%u,%u,%u,%u) ",
> + stat->major, stat->minor,
> + stat->io,
> + stat->rio,
> + stat->wio,
> + stat->rblk,
> + stat->wblk );
> + }
>
> len += sprintf(page + len,
>
> "\nctxt %u\n"
You are changing the order of the fields in /proc/stat. That breaks
compatibility.
Dominik Kubla
--
ScioByte GmbH Zum Schiersteiner Grund 2 55127 Mainz (Germany)
Phone: +49 700 724 629 83 Fax: +49 700 724 629 84
1024D/717F16BB A384 F5F1 F566 5716 5485 27EF 3B00 C007 717F 16BB
Jean-Eric Cuendet wrote:
>
> Hi,
> I've made a new version of IO statistics in kstat that remove the
> previous limitations of MAX_MAJOR
> I've made tests on my machine.
> Could someone test it, please?
> Feedback welcome.
> Bye
> -jec
Thank for your attention and help on updating my disk io patch. Here is
the link to the original patch
http://marc.theaimsgroup.com/?l=linux-kernel&m=100570447604813&w=2. I
re-submitted it a while ago against 2.4 kernels and 2.5.2 kernel. You
can find patches related to disk io statistics at
http://lse.sourceforge.net/resource/diskio/diskio.html
>>+ len += sprintf( page + len, "(%u,%u):(%u,%u,%u,%u,%u) ",
>>+ stat->major, stat->minor,
>>+ stat->io,
>>+ stat->rio,
>>+ stat->wio,
>>+ stat->rblk,
>>+ stat->wblk );
>>+ }
>>
>You are changing the order of the fields in /proc/stat. That breaks
>compatibility.
>
Thanks, you are right.
I'll change that.
-jec