如何在块设备驱动程序中禁用此功能?我的意思是:如以下文档中所述,我想将该“标志”的值设置为 2。我在哪里做呢?最好在块设备驱动程序代码中。
What: /sys/block/<disk>/queue/nomerges
Date: January 2010
Contact:
Description:
Standard I/O elevator operations include attempts to
merge contiguous I/Os. For known random I/O loads these
attempts will always fail and result in extra cycles
being spent in the kernel. This allows one to turn off
this behavior on one of two ways: When set to 1, complex
merge checks are disabled, but the simple one-shot merges
with the previous I/O request are enabled. When set to 2,
all merge tries are disabled. The default value is 0 -
which enables all types of merge tries.