[PATCH] Increase maximum size of dmesg buffer to 16MB.

From: Vinson Lee
Date: Fri Dec 12 2014 - 17:38:41 EST


From: Nate Stahl <stahl@xxxxxxxxxxx>

A full task stack dump of all tasks on a machine can generate more than
4MB of output to dmesg. Dumping this data to the serial console causes
the machine to hang for a number of minutes (an unacceptable impact),
but dumping the same data to memory is feasible if the dmesg buffer is
sized large enough to hold the output. Set to 16MB which will hopefully
be large enough to handle a dump from any of our servers at this time.

Signed-off-by: Nate Stahl <stahl@xxxxxxxxxxx>
Signed-off-by: Vinson Lee <vlee@xxxxxxxxxxx>
---
init/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/init/Kconfig b/init/Kconfig
index 903505e..266a3e8 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -812,7 +812,7 @@ config IKCONFIG_PROC

config LOG_BUF_SHIFT
int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
- range 12 21
+ range 12 24
default 17
depends on PRINTK
help
--
1.9.1

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