diff options
| author | Juhyung Park <[email protected]> | 2023-05-31 23:59:23 +0900 |
|---|---|---|
| committer | GitHub <[email protected]> | 2023-05-31 17:59:23 +0300 |
| commit | 7f8bb428d3023448145199c3a41243d666afe253 (patch) | |
| tree | 6a1db1719f007d0783e64858f8a265c441cf7c53 | |
| parent | d608b6e01064ede7c1d4d112236582cab0456446 (diff) | |
sysctl: tune dirty data writeback policies (#135)
The existing policy sets dirty_background_bytes to 5, which is erroneously
too small that incurs write amplification and read starvations.
Considering a raspi with 2 GiB of RAM, this is 43 million times smaller
than the default Linux policy, which is 10%.
Considering that this will be deployed to mostly read-only system with
emphasis on data integrity (hence needing tighter data writeback), set
this to 256 KiB.
Continuing addressing the overly excessive data writeback policies, also
bump the dirty_writeback_centisecs from 250ms to 1000ms. Any dirty data
written in the past 1 second will be written to the storage.
Signed-off-by: Juhyung Park <[email protected]>
| -rw-r--r-- | configs/os/sysctl.conf | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/configs/os/sysctl.conf b/configs/os/sysctl.conf index 7cfe43b0..abe53aa6 100644 --- a/configs/os/sysctl.conf +++ b/configs/os/sysctl.conf @@ -1,6 +1,7 @@ -# https://github.com/raspberrypi/linux/issues/1753 -vm.dirty_background_bytes = 5 -vm.dirty_writeback_centisecs = 25 +# Overly-aggressive data writeback policies to minimize the chance of data corruption +# Start dirty data writeback when it exceeds 256 KiB or 1s has passed +vm.dirty_background_bytes = 262144 +vm.dirty_writeback_centisecs = 100 # https://groups.google.com/g/meetecho-janus/c/xoWIQfaoJm8 net.core.rmem_default = 500000 |