[PATCH] makedumpfile compression method default to lzo

[WANG Chao]

Lzo is proven faster than zlib, for large memory machine it will
extremely shorten the time for saving vmcore. Let's switch to lzo as the
default compression method for makedumpfile.

The drawback is lzo has a little less compression ratio than zlib. But
considering for most users, speed/time is a more serious concern than
vmcore size. So I think default to lzo will benefit most of the users.

Signed-off-by: WANG Chao <chaowang(a)redhat.com&gt;
---
 dracut-kdump.sh       |  2 +-
 kdump.conf            |  6 +++---
 kexec-kdump-howto.txt | 18 +++++++++---------
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/dracut-kdump.sh b/dracut-kdump.sh
index f38891d..14843f3 100755
--- a/dracut-kdump.sh
+++ b/dracut-kdump.sh
@@ -11,7 +11,7 @@ fi
 set -o pipefail
 KDUMP_PATH="/var/crash"
 CORE_COLLECTOR=""
-DEFAULT_CORE_COLLECTOR="makedumpfile -c --message-level 1 -d 31"
+DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 1 -d 31"
 DMESG_COLLECTOR="/sbin/vmcore-dmesg"
 DEFAULT_ACTION="reboot -f"
 DATEDIR=`date +%Y.%m.%d-%T`
diff --git a/kdump.conf b/kdump.conf
index a0f086a..1bc3064 100644
--- a/kdump.conf
+++ b/kdump.conf
@@ -50,9 +50,9 @@
 #			  automatically be populated with a config file
 #			  appropriate for the running kernel.
 #			  Default core_collector for raw/ssh dump is:
-#			  "makedumpfile -F -c --message-level 1 -d 31".
+#			  "makedumpfile -F -l --message-level 1 -d 31".
 #			  Default core_collector for other targets is:
-#			  "makedumpfile -c --message-level 1 -d 31".
+#			  "makedumpfile -l --message-level 1 -d 31".
 #			  For core_collector format details please refer to
 #			  kexec-kdump-howto.txt or kdump.conf manpage.
 #
@@ -136,7 +136,7 @@
 #ssh user(a)my.server.com
 #sshkey /root/.ssh/kdump_id_rsa
 path /var/crash
-#core_collector makedumpfile -c --message-level 1 -d 31
+#core_collector makedumpfile -l --message-level 1 -d 31
 #core_collector scp
 #kdump_post /var/crash/scripts/kdump-post.sh
 #kdump_pre /var/crash/scripts/kdump-pre.sh
diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
index d70781b..7ffeab9 100644
--- a/kexec-kdump-howto.txt
+++ b/kexec-kdump-howto.txt
@@ -438,7 +438,7 @@ is a dump filtering and compression utility provided with kexec-tools.
On
 some architectures, it can drastically reduce the size of your vmcore files,
 which becomes very useful on systems with large amounts of memory.
 
-A typical setup is 'core_collector makedumpfile -F -c --message-level 1 -d 31',
+A typical setup is 'core_collector makedumpfile -F -l --message-level 1 -d 31',
 but check the output of '/sbin/makedumpfile --help' for a list of all available
 options (-i and -g don't need to be specified, they're automatically taken care
 of). Note that use of makedumpfile requires that the kernel-debuginfo package
@@ -458,11 +458,11 @@ cp --sparse=always /proc/vmcore <dest-path>/vmcore
 
 ex2.
 ---
-core_collector "makedumpfile -c --message-level 1 -d 31"
+core_collector "makedumpfile -l --message-level 1 -d 31"
 
 Above will effectively be translated to:
 
-makedumpfile -c --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
+makedumpfile -l --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
 
 
 For dump targets like raw and ssh, in general, core collector should expect
@@ -482,11 +482,11 @@ cat /proc/vmcore | dd of=<target-device>
 
 ex4.
 ---
-core_collector "makedumpfile -F -c --message-level 1 -d 31"
+core_collector "makedumpfile -F -l --message-level 1 -d 31"
 
 Above will effectively be translated to.
 
-makedumpfile -F -c --message-level 1 -d 31 | dd of=<target-device>
+makedumpfile -F -l --message-level 1 -d 31 | dd of=<target-device>
 
 ssh dumps core_collector examples:
 ---------
@@ -500,11 +500,11 @@ cat /proc/vmcore | ssh <options> <remote-location>
"dd of=path/vmcore"
 
 ex6.
 ---
-core_collector "makedumpfile -F -c --message-level 1 -d 31"
+core_collector "makedumpfile -F -l --message-level 1 -d 31"
 
 Above will effectively be translated to.
 
-makedumpfile -F -c --message-level 1 -d 31 | ssh <options> <remote-location>
"dd of=path/vmcore"
+makedumpfile -F -l --message-level 1 -d 31 | ssh <options> <remote-location>
"dd of=path/vmcore"
 
 There is one exception to standard output rule for ssh dumps. And that is
 scp. As scp can handle ssh destinations for file transfers, one can
@@ -521,9 +521,9 @@ scp /proc/vmcore <user@host>:path/vmcore
 About default core collector
 ----------------------------
 Default core_collector for ssh/raw dump is:
-"makedumpfile -F -c --message-level 1 -d 31".
+"makedumpfile -F -l --message-level 1 -d 31".
 Default core_collector for other targets is:
-"makedumpfile -c --message-level 1 -d 31".
+"makedumpfile -l --message-level 1 -d 31".
 
 Even if core_collector option is commented out in kdump.conf, makedumpfile
 is default core collector and kdump uses it internally.
-- 
1.8.4.2

[Vivek Goyal]

On Wed, Dec 04, 2013 at 07:34:39PM +0800, WANG Chao wrote:
>  Lzo is proven faster than zlib, for large memory machine it will
>  extremely shorten the time for saving vmcore. Let's switch to lzo as the
>  default compression method for makedumpfile.
>  
>  The drawback is lzo has a little less compression ratio than zlib. But
>  considering for most users, speed/time is a more serious concern than
>  vmcore size. So I think default to lzo will benefit most of the users.
>  
>  Signed-off-by: WANG Chao <chaowang(a)redhat.com&gt; 
Agreed. On large RAM machines, lzo is net win. People care more about time
taken to dump as compared to little increase in size of dump. So while
smaller machines might see little bit increase in size of dump, I guess
it should still prove to be a good default across the range of machines.

Acked-by: Vivek Goyal <vgoyal(a)redhat.com&gt;

Thanks
Vivek

>  ---
>   dracut-kdump.sh       |  2 +-
>   kdump.conf            |  6 +++---
>   kexec-kdump-howto.txt | 18 +++++++++---------
>   3 files changed, 13 insertions(+), 13 deletions(-)
>  
>  diff --git a/dracut-kdump.sh b/dracut-kdump.sh
>  index f38891d..14843f3 100755
>  --- a/dracut-kdump.sh
>  +++ b/dracut-kdump.sh
>  @@ -11,7 +11,7 @@ fi
>   set -o pipefail
>   KDUMP_PATH="/var/crash"
>   CORE_COLLECTOR=""
>  -DEFAULT_CORE_COLLECTOR="makedumpfile -c --message-level 1 -d 31"
>  +DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 1 -d 31"
>   DMESG_COLLECTOR="/sbin/vmcore-dmesg"
>   DEFAULT_ACTION="reboot -f"
>   DATEDIR=`date +%Y.%m.%d-%T`
>  diff --git a/kdump.conf b/kdump.conf
>  index a0f086a..1bc3064 100644
>  --- a/kdump.conf
>  +++ b/kdump.conf
>  @@ -50,9 +50,9 @@
>   #			  automatically be populated with a config file
>   #			  appropriate for the running kernel.
>   #			  Default core_collector for raw/ssh dump is:
>  -#			  "makedumpfile -F -c --message-level 1 -d 31".
>  +#			  "makedumpfile -F -l --message-level 1 -d 31".
>   #			  Default core_collector for other targets is:
>  -#			  "makedumpfile -c --message-level 1 -d 31".
>  +#			  "makedumpfile -l --message-level 1 -d 31".
>   #			  For core_collector format details please refer to
>   #			  kexec-kdump-howto.txt or kdump.conf manpage.
>   #
>  @@ -136,7 +136,7 @@
>   #ssh user(a)my.server.com
>   #sshkey /root/.ssh/kdump_id_rsa
>   path /var/crash
>  -#core_collector makedumpfile -c --message-level 1 -d 31
>  +#core_collector makedumpfile -l --message-level 1 -d 31
>   #core_collector scp
>   #kdump_post /var/crash/scripts/kdump-post.sh
>   #kdump_pre /var/crash/scripts/kdump-pre.sh
>  diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
>  index d70781b..7ffeab9 100644
>  --- a/kexec-kdump-howto.txt
>  +++ b/kexec-kdump-howto.txt
>  @@ -438,7 +438,7 @@ is a dump filtering and compression utility provided with
> kexec-tools. On
>   some architectures, it can drastically reduce the size of your vmcore files,
>   which becomes very useful on systems with large amounts of memory.
>   
>  -A typical setup is 'core_collector makedumpfile -F -c --message-level 1 -d 31',
>  +A typical setup is 'core_collector makedumpfile -F -l --message-level 1 -d 31',
>   but check the output of '/sbin/makedumpfile --help' for a list of all available
>   options (-i and -g don't need to be specified, they're automatically taken care
>   of). Note that use of makedumpfile requires that the kernel-debuginfo package
>  @@ -458,11 +458,11 @@ cp --sparse=always /proc/vmcore <dest-path>/vmcore
>   
>   ex2.
>   ---
>  -core_collector "makedumpfile -c --message-level 1 -d 31"
>  +core_collector "makedumpfile -l --message-level 1 -d 31"
>   
>   Above will effectively be translated to:
>   
>  -makedumpfile -c --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>  +makedumpfile -l --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>   
>   
>   For dump targets like raw and ssh, in general, core collector should expect
>  @@ -482,11 +482,11 @@ cat /proc/vmcore | dd of=<target-device>
>   
>   ex4.
>   ---
>  -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>   
>   Above will effectively be translated to.
>   
>  -makedumpfile -F -c --message-level 1 -d 31 | dd of=<target-device>
>  +makedumpfile -F -l --message-level 1 -d 31 | dd of=<target-device>
>   
>   ssh dumps core_collector examples:
>   ---------
>  @@ -500,11 +500,11 @@ cat /proc/vmcore | ssh <options> <remote-location>
> "dd of=path/vmcore"
>   
>   ex6.
>   ---
>  -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>   
>   Above will effectively be translated to.
>   
>  -makedumpfile -F -c --message-level 1 -d 31 | ssh <options> <remote-location>
> "dd of=path/vmcore"
>  +makedumpfile -F -l --message-level 1 -d 31 | ssh <options> <remote-location>
> "dd of=path/vmcore"
>   
>   There is one exception to standard output rule for ssh dumps. And that is
>   scp. As scp can handle ssh destinations for file transfers, one can
>  @@ -521,9 +521,9 @@ scp /proc/vmcore <user@host>:path/vmcore
>   About default core collector
>   ----------------------------
>   Default core_collector for ssh/raw dump is:
>  -"makedumpfile -F -c --message-level 1 -d 31".
>  +"makedumpfile -F -l --message-level 1 -d 31".
>   Default core_collector for other targets is:
>  -"makedumpfile -c --message-level 1 -d 31".
>  +"makedumpfile -l --message-level 1 -d 31".
>   
>   Even if core_collector option is commented out in kdump.conf, makedumpfile
>   is default core collector and kdump uses it internally.
>  -- 
>  1.8.4.2

[Dave Young]

On 12/04/13 at 04:12pm, Vivek Goyal wrote:
>  On Wed, Dec 04, 2013 at 07:34:39PM +0800, WANG Chao wrote:
>  > Lzo is proven faster than zlib, for large memory machine it will
>  > extremely shorten the time for saving vmcore. Let's switch to lzo as the
>  > default compression method for makedumpfile.
>  > 
>  > The drawback is lzo has a little less compression ratio than zlib. But
>  > considering for most users, speed/time is a more serious concern than
>  > vmcore size. So I think default to lzo will benefit most of the users.
>  > 
>  > Signed-off-by: WANG Chao <chaowang(a)redhat.com&gt;
>  
>  Agreed. On large RAM machines, lzo is net win. People care more about time
>  taken to dump as compared to little increase in size of dump. So while
>  smaller machines might see little bit increase in size of dump, I guess
>  it should still prove to be a good default across the range of machines.
>  
>  Acked-by: Vivek Goyal <vgoyal(a)redhat.com&gt;
>  
>  Thanks
>  Vivek
>  
>  > ---
>  >  dracut-kdump.sh       |  2 +-
>  >  kdump.conf            |  6 +++---
>  >  kexec-kdump-howto.txt | 18 +++++++++---------
>  >  3 files changed, 13 insertions(+), 13 deletions(-) 
Looks like kdump.conf.5 was missed. The manpage also need update.

Thanks for the patch.

>  > 
>  > diff --git a/dracut-kdump.sh b/dracut-kdump.sh
>  > index f38891d..14843f3 100755
>  > --- a/dracut-kdump.sh
>  > +++ b/dracut-kdump.sh
>  > @@ -11,7 +11,7 @@ fi
>  >  set -o pipefail
>  >  KDUMP_PATH="/var/crash"
>  >  CORE_COLLECTOR=""
>  > -DEFAULT_CORE_COLLECTOR="makedumpfile -c --message-level 1 -d 31"
>  > +DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 1 -d 31"
>  >  DMESG_COLLECTOR="/sbin/vmcore-dmesg"
>  >  DEFAULT_ACTION="reboot -f"
>  >  DATEDIR=`date +%Y.%m.%d-%T`
>  > diff --git a/kdump.conf b/kdump.conf
>  > index a0f086a..1bc3064 100644
>  > --- a/kdump.conf
>  > +++ b/kdump.conf
>  > @@ -50,9 +50,9 @@
>  >  #			  automatically be populated with a config file
>  >  #			  appropriate for the running kernel.
>  >  #			  Default core_collector for raw/ssh dump is:
>  > -#			  "makedumpfile -F -c --message-level 1 -d 31".
>  > +#			  "makedumpfile -F -l --message-level 1 -d 31".
>  >  #			  Default core_collector for other targets is:
>  > -#			  "makedumpfile -c --message-level 1 -d 31".
>  > +#			  "makedumpfile -l --message-level 1 -d 31".
>  >  #			  For core_collector format details please refer to
>  >  #			  kexec-kdump-howto.txt or kdump.conf manpage.
>  >  #
>  > @@ -136,7 +136,7 @@
>  >  #ssh user(a)my.server.com
>  >  #sshkey /root/.ssh/kdump_id_rsa
>  >  path /var/crash
>  > -#core_collector makedumpfile -c --message-level 1 -d 31
>  > +#core_collector makedumpfile -l --message-level 1 -d 31
>  >  #core_collector scp
>  >  #kdump_post /var/crash/scripts/kdump-post.sh
>  >  #kdump_pre /var/crash/scripts/kdump-pre.sh
>  > diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
>  > index d70781b..7ffeab9 100644
>  > --- a/kexec-kdump-howto.txt
>  > +++ b/kexec-kdump-howto.txt
>  > @@ -438,7 +438,7 @@ is a dump filtering and compression utility provided with
> kexec-tools. On
>  >  some architectures, it can drastically reduce the size of your vmcore files,
>  >  which becomes very useful on systems with large amounts of memory.
>  >  
>  > -A typical setup is 'core_collector makedumpfile -F -c --message-level 1 -d
> 31',
>  > +A typical setup is 'core_collector makedumpfile -F -l --message-level 1 -d
> 31',
>  >  but check the output of '/sbin/makedumpfile --help' for a list of all
> available
>  >  options (-i and -g don't need to be specified, they're automatically taken
> care
>  >  of). Note that use of makedumpfile requires that the kernel-debuginfo package
>  > @@ -458,11 +458,11 @@ cp --sparse=always /proc/vmcore <dest-path>/vmcore
>  >  
>  >  ex2.
>  >  ---
>  > -core_collector "makedumpfile -c --message-level 1 -d 31"
>  > +core_collector "makedumpfile -l --message-level 1 -d 31"
>  >  
>  >  Above will effectively be translated to:
>  >  
>  > -makedumpfile -c --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>  > +makedumpfile -l --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>  >  
>  >  
>  >  For dump targets like raw and ssh, in general, core collector should expect
>  > @@ -482,11 +482,11 @@ cat /proc/vmcore | dd of=<target-device>
>  >  
>  >  ex4.
>  >  ---
>  > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  >  
>  >  Above will effectively be translated to.
>  >  
>  > -makedumpfile -F -c --message-level 1 -d 31 | dd of=<target-device>
>  > +makedumpfile -F -l --message-level 1 -d 31 | dd of=<target-device>
>  >  
>  >  ssh dumps core_collector examples:
>  >  ---------
>  > @@ -500,11 +500,11 @@ cat /proc/vmcore | ssh <options> <remote-location>
> "dd of=path/vmcore"
>  >  
>  >  ex6.
>  >  ---
>  > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  >  
>  >  Above will effectively be translated to.
>  >  
>  > -makedumpfile -F -c --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > +makedumpfile -F -l --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  >  
>  >  There is one exception to standard output rule for ssh dumps. And that is
>  >  scp. As scp can handle ssh destinations for file transfers, one can
>  > @@ -521,9 +521,9 @@ scp /proc/vmcore <user@host>:path/vmcore
>  >  About default core collector
>  >  ----------------------------
>  >  Default core_collector for ssh/raw dump is:
>  > -"makedumpfile -F -c --message-level 1 -d 31".
>  > +"makedumpfile -F -l --message-level 1 -d 31".
>  >  Default core_collector for other targets is:
>  > -"makedumpfile -c --message-level 1 -d 31".
>  > +"makedumpfile -l --message-level 1 -d 31".
>  >  
>  >  Even if core_collector option is commented out in kdump.conf, makedumpfile
>  >  is default core collector and kdump uses it internally.
>  > -- 
>  > 1.8.4.2

[WANG Chao]

On 12/05/13 at 09:51am, Dave Young wrote:
>  On 12/04/13 at 04:12pm, Vivek Goyal wrote:
>  > On Wed, Dec 04, 2013 at 07:34:39PM +0800, WANG Chao wrote:
>  > > Lzo is proven faster than zlib, for large memory machine it will
>  > > extremely shorten the time for saving vmcore. Let's switch to lzo as the
>  > > default compression method for makedumpfile.
>  > > 
>  > > The drawback is lzo has a little less compression ratio than zlib. But
>  > > considering for most users, speed/time is a more serious concern than
>  > > vmcore size. So I think default to lzo will benefit most of the users.
>  > > 
>  > > Signed-off-by: WANG Chao <chaowang(a)redhat.com&gt;
>  > 
>  > Agreed. On large RAM machines, lzo is net win. People care more about time
>  > taken to dump as compared to little increase in size of dump. So while
>  > smaller machines might see little bit increase in size of dump, I guess
>  > it should still prove to be a good default across the range of machines.
>  > 
>  > Acked-by: Vivek Goyal <vgoyal(a)redhat.com&gt;
>  > 
>  > Thanks
>  > Vivek
>  > 
>  > > ---
>  > >  dracut-kdump.sh       |  2 +-
>  > >  kdump.conf            |  6 +++---
>  > >  kexec-kdump-howto.txt | 18 +++++++++---------
>  > >  3 files changed, 13 insertions(+), 13 deletions(-)
>  
>  Looks like kdump.conf.5 was missed. The manpage also need update. 
We don't have kdump.conf.5. And I don't think we need that.

we don't have kdump.conf.5 in RHEL5/6 and we already detail everything
in kdump.conf and kexec-kdump-howto.txt. So providing a man page for
kdump.conf is a good idea, however we won't benefit much from it.

Thanks
WANG Chao

>  
>  Thanks for the patch.
>  
>  > > 
>  > > diff --git a/dracut-kdump.sh b/dracut-kdump.sh
>  > > index f38891d..14843f3 100755
>  > > --- a/dracut-kdump.sh
>  > > +++ b/dracut-kdump.sh
>  > > @@ -11,7 +11,7 @@ fi
>  > >  set -o pipefail
>  > >  KDUMP_PATH="/var/crash"
>  > >  CORE_COLLECTOR=""
>  > > -DEFAULT_CORE_COLLECTOR="makedumpfile -c --message-level 1 -d 31"
>  > > +DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 1 -d 31"
>  > >  DMESG_COLLECTOR="/sbin/vmcore-dmesg"
>  > >  DEFAULT_ACTION="reboot -f"
>  > >  DATEDIR=`date +%Y.%m.%d-%T`
>  > > diff --git a/kdump.conf b/kdump.conf
>  > > index a0f086a..1bc3064 100644
>  > > --- a/kdump.conf
>  > > +++ b/kdump.conf
>  > > @@ -50,9 +50,9 @@
>  > >  #			  automatically be populated with a config file
>  > >  #			  appropriate for the running kernel.
>  > >  #			  Default core_collector for raw/ssh dump is:
>  > > -#			  "makedumpfile -F -c --message-level 1 -d 31".
>  > > +#			  "makedumpfile -F -l --message-level 1 -d 31".
>  > >  #			  Default core_collector for other targets is:
>  > > -#			  "makedumpfile -c --message-level 1 -d 31".
>  > > +#			  "makedumpfile -l --message-level 1 -d 31".
>  > >  #			  For core_collector format details please refer to
>  > >  #			  kexec-kdump-howto.txt or kdump.conf manpage.
>  > >  #
>  > > @@ -136,7 +136,7 @@
>  > >  #ssh user(a)my.server.com
>  > >  #sshkey /root/.ssh/kdump_id_rsa
>  > >  path /var/crash
>  > > -#core_collector makedumpfile -c --message-level 1 -d 31
>  > > +#core_collector makedumpfile -l --message-level 1 -d 31
>  > >  #core_collector scp
>  > >  #kdump_post /var/crash/scripts/kdump-post.sh
>  > >  #kdump_pre /var/crash/scripts/kdump-pre.sh
>  > > diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
>  > > index d70781b..7ffeab9 100644
>  > > --- a/kexec-kdump-howto.txt
>  > > +++ b/kexec-kdump-howto.txt
>  > > @@ -438,7 +438,7 @@ is a dump filtering and compression utility provided with
> kexec-tools. On
>  > >  some architectures, it can drastically reduce the size of your vmcore files,
>  > >  which becomes very useful on systems with large amounts of memory.
>  > >  
>  > > -A typical setup is 'core_collector makedumpfile -F -c --message-level 1 -d
> 31',
>  > > +A typical setup is 'core_collector makedumpfile -F -l --message-level 1 -d
> 31',
>  > >  but check the output of '/sbin/makedumpfile --help' for a list of all
> available
>  > >  options (-i and -g don't need to be specified, they're automatically
> taken care
>  > >  of). Note that use of makedumpfile requires that the kernel-debuginfo package
>  > > @@ -458,11 +458,11 @@ cp --sparse=always /proc/vmcore <dest-path>/vmcore
>  > >  
>  > >  ex2.
>  > >  ---
>  > > -core_collector "makedumpfile -c --message-level 1 -d 31"
>  > > +core_collector "makedumpfile -l --message-level 1 -d 31"
>  > >  
>  > >  Above will effectively be translated to:
>  > >  
>  > > -makedumpfile -c --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>  > > +makedumpfile -l --message-level 1 -d 31 /proc/vmcore <dest-path>/vmcore
>  > >  
>  > >  
>  > >  For dump targets like raw and ssh, in general, core collector should expect
>  > > @@ -482,11 +482,11 @@ cat /proc/vmcore | dd of=<target-device>
>  > >  
>  > >  ex4.
>  > >  ---
>  > > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  > >  
>  > >  Above will effectively be translated to.
>  > >  
>  > > -makedumpfile -F -c --message-level 1 -d 31 | dd of=<target-device>
>  > > +makedumpfile -F -l --message-level 1 -d 31 | dd of=<target-device>
>  > >  
>  > >  ssh dumps core_collector examples:
>  > >  ---------
>  > > @@ -500,11 +500,11 @@ cat /proc/vmcore | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > >  
>  > >  ex6.
>  > >  ---
>  > > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  > >  
>  > >  Above will effectively be translated to.
>  > >  
>  > > -makedumpfile -F -c --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > > +makedumpfile -F -l --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > >  
>  > >  There is one exception to standard output rule for ssh dumps. And that is
>  > >  scp. As scp can handle ssh destinations for file transfers, one can
>  > > @@ -521,9 +521,9 @@ scp /proc/vmcore <user@host>:path/vmcore
>  > >  About default core collector
>  > >  ----------------------------
>  > >  Default core_collector for ssh/raw dump is:
>  > > -"makedumpfile -F -c --message-level 1 -d 31".
>  > > +"makedumpfile -F -l --message-level 1 -d 31".
>  > >  Default core_collector for other targets is:
>  > > -"makedumpfile -c --message-level 1 -d 31".
>  > > +"makedumpfile -l --message-level 1 -d 31".
>  > >  
>  > >  Even if core_collector option is commented out in kdump.conf, makedumpfile
>  > >  is default core collector and kdump uses it internally.
>  > > -- 
>  > > 1.8.4.2

[WANG Chao]

On 12/05/13 at 12:18pm, WANG Chao wrote:
>  On 12/05/13 at 09:51am, Dave Young wrote:
>  > On 12/04/13 at 04:12pm, Vivek Goyal wrote:
>  > > On Wed, Dec 04, 2013 at 07:34:39PM +0800, WANG Chao wrote:
>  > > > Lzo is proven faster than zlib, for large memory machine it will
>  > > > extremely shorten the time for saving vmcore. Let's switch to lzo as
> the
>  > > > default compression method for makedumpfile.
>  > > > 
>  > > > The drawback is lzo has a little less compression ratio than zlib. But
>  > > > considering for most users, speed/time is a more serious concern than
>  > > > vmcore size. So I think default to lzo will benefit most of the users.
>  > > > 
>  > > > Signed-off-by: WANG Chao <chaowang(a)redhat.com&gt;
>  > > 
>  > > Agreed. On large RAM machines, lzo is net win. People care more about time
>  > > taken to dump as compared to little increase in size of dump. So while
>  > > smaller machines might see little bit increase in size of dump, I guess
>  > > it should still prove to be a good default across the range of machines.
>  > > 
>  > > Acked-by: Vivek Goyal <vgoyal(a)redhat.com&gt;
>  > > 
>  > > Thanks
>  > > Vivek
>  > > 
>  > > > ---
>  > > >  dracut-kdump.sh       |  2 +-
>  > > >  kdump.conf            |  6 +++---
>  > > >  kexec-kdump-howto.txt | 18 +++++++++---------
>  > > >  3 files changed, 13 insertions(+), 13 deletions(-)
>  > 
>  > Looks like kdump.conf.5 was missed. The manpage also need update.
>  
>  We don't have kdump.conf.5. And I don't think we need that.
>  
>  we don't have kdump.conf.5 in RHEL5/6 and we already detail everything
>  in kdump.conf and kexec-kdump-howto.txt. So providing a man page for
>  kdump.conf is a good idea, however we won't benefit much from it. 
Ignore this. I mis-read your email.

Sorry
WANG Chao

>  
>  Thanks
>  WANG Chao
>  
>  > 
>  > Thanks for the patch.
>  > 
>  > > > 
>  > > > diff --git a/dracut-kdump.sh b/dracut-kdump.sh
>  > > > index f38891d..14843f3 100755
>  > > > --- a/dracut-kdump.sh
>  > > > +++ b/dracut-kdump.sh
>  > > > @@ -11,7 +11,7 @@ fi
>  > > >  set -o pipefail
>  > > >  KDUMP_PATH="/var/crash"
>  > > >  CORE_COLLECTOR=""
>  > > > -DEFAULT_CORE_COLLECTOR="makedumpfile -c --message-level 1 -d
> 31"
>  > > > +DEFAULT_CORE_COLLECTOR="makedumpfile -l --message-level 1 -d
> 31"
>  > > >  DMESG_COLLECTOR="/sbin/vmcore-dmesg"
>  > > >  DEFAULT_ACTION="reboot -f"
>  > > >  DATEDIR=`date +%Y.%m.%d-%T`
>  > > > diff --git a/kdump.conf b/kdump.conf
>  > > > index a0f086a..1bc3064 100644
>  > > > --- a/kdump.conf
>  > > > +++ b/kdump.conf
>  > > > @@ -50,9 +50,9 @@
>  > > >  #			  automatically be populated with a config file
>  > > >  #			  appropriate for the running kernel.
>  > > >  #			  Default core_collector for raw/ssh dump is:
>  > > > -#			  "makedumpfile -F -c --message-level 1 -d 31".
>  > > > +#			  "makedumpfile -F -l --message-level 1 -d 31".
>  > > >  #			  Default core_collector for other targets is:
>  > > > -#			  "makedumpfile -c --message-level 1 -d 31".
>  > > > +#			  "makedumpfile -l --message-level 1 -d 31".
>  > > >  #			  For core_collector format details please refer to
>  > > >  #			  kexec-kdump-howto.txt or kdump.conf manpage.
>  > > >  #
>  > > > @@ -136,7 +136,7 @@
>  > > >  #ssh user(a)my.server.com
>  > > >  #sshkey /root/.ssh/kdump_id_rsa
>  > > >  path /var/crash
>  > > > -#core_collector makedumpfile -c --message-level 1 -d 31
>  > > > +#core_collector makedumpfile -l --message-level 1 -d 31
>  > > >  #core_collector scp
>  > > >  #kdump_post /var/crash/scripts/kdump-post.sh
>  > > >  #kdump_pre /var/crash/scripts/kdump-pre.sh
>  > > > diff --git a/kexec-kdump-howto.txt b/kexec-kdump-howto.txt
>  > > > index d70781b..7ffeab9 100644
>  > > > --- a/kexec-kdump-howto.txt
>  > > > +++ b/kexec-kdump-howto.txt
>  > > > @@ -438,7 +438,7 @@ is a dump filtering and compression utility provided
> with kexec-tools. On
>  > > >  some architectures, it can drastically reduce the size of your vmcore
> files,
>  > > >  which becomes very useful on systems with large amounts of memory.
>  > > >  
>  > > > -A typical setup is 'core_collector makedumpfile -F -c --message-level
> 1 -d 31',
>  > > > +A typical setup is 'core_collector makedumpfile -F -l --message-level
> 1 -d 31',
>  > > >  but check the output of '/sbin/makedumpfile --help' for a list of
> all available
>  > > >  options (-i and -g don't need to be specified, they're
> automatically taken care
>  > > >  of). Note that use of makedumpfile requires that the kernel-debuginfo
> package
>  > > > @@ -458,11 +458,11 @@ cp --sparse=always /proc/vmcore
> <dest-path>/vmcore
>  > > >  
>  > > >  ex2.
>  > > >  ---
>  > > > -core_collector "makedumpfile -c --message-level 1 -d 31"
>  > > > +core_collector "makedumpfile -l --message-level 1 -d 31"
>  > > >  
>  > > >  Above will effectively be translated to:
>  > > >  
>  > > > -makedumpfile -c --message-level 1 -d 31 /proc/vmcore
> <dest-path>/vmcore
>  > > > +makedumpfile -l --message-level 1 -d 31 /proc/vmcore
> <dest-path>/vmcore
>  > > >  
>  > > >  
>  > > >  For dump targets like raw and ssh, in general, core collector should
> expect
>  > > > @@ -482,11 +482,11 @@ cat /proc/vmcore | dd of=<target-device>
>  > > >  
>  > > >  ex4.
>  > > >  ---
>  > > > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > > > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  > > >  
>  > > >  Above will effectively be translated to.
>  > > >  
>  > > > -makedumpfile -F -c --message-level 1 -d 31 | dd of=<target-device>
>  > > > +makedumpfile -F -l --message-level 1 -d 31 | dd of=<target-device>
>  > > >  
>  > > >  ssh dumps core_collector examples:
>  > > >  ---------
>  > > > @@ -500,11 +500,11 @@ cat /proc/vmcore | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > > >  
>  > > >  ex6.
>  > > >  ---
>  > > > -core_collector "makedumpfile -F -c --message-level 1 -d 31"
>  > > > +core_collector "makedumpfile -F -l --message-level 1 -d 31"
>  > > >  
>  > > >  Above will effectively be translated to.
>  > > >  
>  > > > -makedumpfile -F -c --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > > > +makedumpfile -F -l --message-level 1 -d 31 | ssh <options>
> <remote-location> "dd of=path/vmcore"
>  > > >  
>  > > >  There is one exception to standard output rule for ssh dumps. And that
> is
>  > > >  scp. As scp can handle ssh destinations for file transfers, one can
>  > > > @@ -521,9 +521,9 @@ scp /proc/vmcore <user@host>:path/vmcore
>  > > >  About default core collector
>  > > >  ----------------------------
>  > > >  Default core_collector for ssh/raw dump is:
>  > > > -"makedumpfile -F -c --message-level 1 -d 31".
>  > > > +"makedumpfile -F -l --message-level 1 -d 31".
>  > > >  Default core_collector for other targets is:
>  > > > -"makedumpfile -c --message-level 1 -d 31".
>  > > > +"makedumpfile -l --message-level 1 -d 31".
>  > > >  
>  > > >  Even if core_collector option is commented out in kdump.conf,
> makedumpfile
>  > > >  is default core collector and kdump uses it internally.
>  > > > -- 
>  > > > 1.8.4.2