Commit f17a32e97e (let LOG_BUF_SHIFT default to 17) from 2008 was the last time, the the default log buffer size bump was increased.
Machines have evolved, and on current hardware, enough memory is present, and some devices have over 200 PCI devices, like a two socket Skylake-E server, resulting a lot of lines. Therefore, increase the default from 128 KB to 512 KB. Anyone, with limited memory, can still lower it. Signed-off-by: Paul Menzel <pmen...@molgen.mpg.de> Cc: linux-kernel@vger.kernel.org --- v2: New patch in series. Is sending it to linux-kernel enough? If not, who to send it also to? init/Kconfig | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 9dc607e3806f..13df63517cc2 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -681,9 +681,9 @@ config IKHEADERS kheaders.ko is built which can be loaded on-demand to get access to headers. config LOG_BUF_SHIFT - int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" + int "Kernel log buffer size (17 => 128KB, 19 => 512KB)" range 12 25 - default 17 + default 19 depends on PRINTK help Select the minimal kernel log buffer size as a power of 2. @@ -692,6 +692,8 @@ config LOG_BUF_SHIFT by "log_buf_len" boot parameter. Examples: + 19 => 512 KB + 18 => 256 KB 17 => 128 KB 16 => 64 KB 15 => 32 KB @@ -718,7 +720,7 @@ config LOG_CPU_MAX_BUF_SHIFT with more CPUs. Therefore this value is used only when the sum of contributions is greater than the half of the default kernel ring buffer as defined by LOG_BUF_SHIFT. The default values are set - so that more than 16 CPUs are needed to trigger the allocation. + so that more than 64 CPUs are needed to trigger the allocation. Also this option is ignored when "log_buf_len" kernel parameter is used as it forces an exact (power of two) size of the ring buffer. -- 2.28.0