disk cache

QNX Newsgroups (Archives) qdn.public.qnxrtp.installation
1

Hi!

how can i change disk cache configure?
i.e. cache size, write delay etc
I see that i should configure io-blk.so –
and my question – how do it?

Thanks
vasa

2

pardon, i have found answer.

but there is another question:
can i increase performance of qnx file system to write?
i have very big logs which brakes CPU !!!

why is qnx FS is so slow?

–
Thanks
vasa

3

“vasa” <vv40in@newmail.ru> wrote in message news:ampmq5$ssb$1@inn.qnx.com…

pardon, i have found answer.

but there is another question:
can i increase performance of qnx file system to write?

If your system is using DMA already, there isn’t much you can do.

i have very big logs which brakes CPU !!!

Brakes CPU, well usually while writing files the CPU is free to do other
stuff. I will slow the application that writes the file but unless you have
very slow CPU it shouldn’t affect CPU by much. On my machine PII 400
writing as fast as possible (with DMA) only takes 20% of CPU.

why is qnx FS is so slow?

–
Thanks
vasa

4

“Mario Charest” postmaster@127.0.0.1 wrote in message
news:amr4lp$1ds$1@inn.qnx.com…

“vasa” <> vv40in@newmail.ru> > wrote in message
news:ampmq5$ssb$> 1@inn.qnx.com> …
pardon, i have found answer.

but there is another question:
can i increase performance of qnx file system to write?

If your system is using DMA already, there isn’t much you can do.

i have very big logs which brakes CPU !!!

Brakes CPU, well usually while writing files the CPU is free to do other
stuff. I will slow the application that writes the file but unless you
have
very slow CPU it shouldn’t affect CPU by much. On my machine PII 400
writing as fast as possible (with DMA) only takes 20% of CPU.

my box has PII-800. and 1/2 of program work time is writing to disk if
program generates logs.
but on linux – i dont see difference beyween the following cases:

  • program generates logs
  • program does not generate logs.
    (on the same CPU with the same disk)
    IMHO – qxn file system is
    either none-effective or i dont understand how ot configure it.
    if 2nd case – plz, explain me how to configure qn fs to do it faster


why is qnx FS is so slow?

–
Thanks
vasa

\

5

my box has PII-800. and 1/2 of program work time is writing to disk if
program generates logs.
but on linux – i dont see difference beyween the following cases:

  • program generates logs
  • program does not generate logs.
    (on the same CPU with the same disk)
    IMHO – qxn file system is
    either none-effective or i dont understand how ot configure it.
    if 2nd case – plz, explain me how to configure qn fs to do it faster

QNX doesn’t do as good of a job as Linux making use of DMA on all platform.
On way I know to check if DMA is enable is to test the performance. Without
DMA you will get 2-3Mbytes/sec read rate. If DMA isn’t enable you might
want to add an option to enable it (check usage of io-block) or in fact
remove the option which disable it :wink:

Unless the write speed of your process if rather low I’m surprise there is
no CPU load in Linux when logging to file.


why is qnx FS is so slow?

–
Thanks
vasa



\

6

Thanks ,

QNX doesn’t do as good of a job as Linux making use of DMA on all
platform.
On way I know to check if DMA is enable is to test the performance.
Without
DMA you will get 2-3Mbytes/sec read rate. If DMA isn’t enable you might
want to add an option to enable it (check usage of io-block) or in fact
remove the option which disable it > :wink:
i use DMA



Unless the write speed of your process if rather low I’m surprise there is
no CPU load in Linux when logging to file.
i guess that linux better apportions CPU load

and it starts starts write to disk from cache when CPU free?

Thanks
vasa

7

i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

Thanks
vasa

8

This is what I had to do in order to the disk cache setup with 2 MB cache
(the opposite of what you are trying to accomplish):

Start disk and drivers

[pri=10o] PATH=/proc/boot devb-eide blk
cache=2m,noatime,delwri=0,commit=high,automount=cd0:/fs/cd0 auto=partition
dos exec=all cam quiet eide dma,ioport=0x1f0,irq=14 eide
dma,ioport=0x170,irq=15 &
[pri=10o] PATH=/proc/boot
diskboot -xdevb-eide -s -b1 -D0 -odevc-con,-n4

Otherwise I don’t think the cache option will have any effect. It is pretty
simple to test with

pidin -f Nd | grep eide

which will tell you how much memory devb-eide is currently using.

–
Jens


“vasa” <vv40in@newmail.ru> wrote in message news:amsqn6$9j5$1@inn.qnx.com…

i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot
diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

Thanks
vasa

9

I forgot to say that my example also has some options on the devb-eide whcih
causes it to
have a quick commit strategy, which you probably don’t want. But you can
look at the cache
setup part as reference.

–
Jens

“Jens H Jorgensen” <jhj@remove-nospam-videk.com> wrote in message
news:amssd4$ajg$1@inn.qnx.com…

This is what I had to do in order to the disk cache setup with 2 MB cache
(the opposite of what you are trying to accomplish):

Start disk and drivers

[pri=10o] PATH=/proc/boot devb-eide blk
cache=2m,noatime,delwri=0,commit=high,automount=cd0:/fs/cd0 auto=partition
dos exec=all cam quiet eide dma,ioport=0x1f0,irq=14 eide
dma,ioport=0x170,irq=15 &
[pri=10o] PATH=/proc/boot
diskboot -xdevb-eide -s -b1 -D0 -odevc-con,-n4

Otherwise I don’t think the cache option will have any effect. It is
pretty
simple to test with

pidin -f Nd | grep eide

which will tell you how much memory devb-eide is currently using.

–
Jens


“vasa” <> vv40in@newmail.ru> > wrote in message
news:amsqn6$9j5$> 1@inn.qnx.com> …
i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot
diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

Thanks
vasa

\

10

“vasa” <vv40in@newmail.ru> wrote in message news:amsmrq$6nc$1@inn.qnx.com…

Thanks ,

QNX doesn’t do as good of a job as Linux making use of DMA on all
platform.
On way I know to check if DMA is enable is to test the performance.
Without
DMA you will get 2-3Mbytes/sec read rate. If DMA isn’t enable you might
want to add an option to enable it (check usage of io-block) or in fact
remove the option which disable it > :wink:
i use DMA

Unless the write speed of your process if rather low I’m surprise there
is
no CPU load in Linux when logging to file.
i guess that linux better apportions CPU load
and it starts starts write to disk from cache when CPU free?

I doubt it

Thanks
vasa

11

i have use this strings
but my machine hangs during boot time.
(but before i check [sin -Pdevb-eide arg] – i/o parameters the same)
Q: why does it hung?

“Jens H Jorgensen” <jhj@remove-nospam-videk.com> wrote in message
news:amssd4$ajg$1@inn.qnx.com…

This is what I had to do in order to the disk cache setup with 2 MB cache
(the opposite of what you are trying to accomplish):

Start disk and drivers

[pri=10o] PATH=/proc/boot devb-eide blk
cache=2m,noatime,delwri=0,commit=high,automount=cd0:/fs/cd0 auto=partition
dos exec=all cam quiet eide dma,ioport=0x1f0,irq=14 eide
dma,ioport=0x170,irq=15 &
[pri=10o] PATH=/proc/boot
diskboot -xdevb-eide -s -b1 -D0 -odevc-con,-n4

Otherwise I don’t think the cache option will have any effect. It is
pretty
simple to test with

pidin -f Nd | grep eide

which will tell you how much memory devb-eide is currently using.

–
Jens


“vasa” <> vv40in@newmail.ru> > wrote in message
news:amsqn6$9j5$> 1@inn.qnx.com> …
i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot
diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

Thanks
vasa

\

12

Vasa

I hope you didn’t take the below text exactly as it is listed because the
news client
introduced new lines. Below where you see the [pri=10o] is the beginning of
each new line.

I don’t know mkifs takes \ for line continuation but here is how it would
look like
if you can use \

Start disk and drivers

[pri=10o] PATH=/proc/boot devb-eide blk
cache=2m,noatime,delwri=0,commit=high,automount=cd0:/fs/cd0 auto=partition
dos exec=all cam quiet eide dma,ioport=0x1f0,irq=14 eide
dma,ioport=0x170,irq=15 &

[pri=10o] PATH=/proc/boot
diskboot -xdevb-eide -s -b1 -D0 -odevc-con,-n4


There are basically only two lines above each starting with [pri…].

–
Jens

“vasa” <vv40in@newmail.ru> wrote in message news:amuefm$ei2$1@inn.qnx.com…

i have use this strings
but my machine hangs during boot time.
(but before i check [sin -Pdevb-eide arg] – i/o parameters the same)
Q: why does it hung?

“Jens H Jorgensen” <> jhj@remove-nospam-videk.com> > wrote in message
news:amssd4$ajg$> 1@inn.qnx.com> …
This is what I had to do in order to the disk cache setup with 2 MB
cache
(the opposite of what you are trying to accomplish):

Start disk and drivers

[pri=10o] PATH=/proc/boot devb-eide blk
cache=2m,noatime,delwri=0,commit=high,automount=cd0:/fs/cd0
auto=partition
dos exec=all cam quiet eide dma,ioport=0x1f0,irq=14 eide
dma,ioport=0x170,irq=15 &
[pri=10o] PATH=/proc/boot
diskboot -xdevb-eide -s -b1 -D0 -odevc-con,-n4

Otherwise I don’t think the cache option will have any effect. It is
pretty
simple to test with

pidin -f Nd | grep eide

which will tell you how much memory devb-eide is currently using.

–
Jens


“vasa” <> vv40in@newmail.ru> > wrote in message
news:amsqn6$9j5$> 1@inn.qnx.com> …
i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot
diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

Thanks
vasa



\

13

vasa <vv40in@newmail.ru> wrote in article <amsqn6$9j5$1@inn.qnx.com>…

i use:

[+script] startup-script = {
procmgr_symlink …/…/proc/boot/libc.so.2 /usr/lib/ldqnx.so.2
[pri=10o] PATH=/proc/boot diskboot -b1 -D1 -odevc-con,-n4 -o"devb-eide,blk
cache=50m,delwri=5"
}

is it right?

It’s right in accordance with documentation, but it doesn’t work. Actually (I checked it in 6.1)
the devb-eide gets the default arguments and your arguments are at end of command line, of course
the devb-eide ignores the extra arguments. Please follow up the Jen’s advise or read the discussion
about restart the disk driver, I believe “shell programming question” dated 30.08.02 in
qdn.public.qnxrtp.os newsgroup.
Best regards,

Eduard.
ed1k at ukr dot net


Thanks
vasa
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