Add DWPD (Drive Writes Per Day) rate limiting to control L2ARC write
speeds and protect SSD endurance. Write rate is constrained by the
minimum of l2arc_write_max and DWPD-calculated budget. Devices
accumulate unused write budget over 24-hour periods with automatic reset
and carry-over. Writes occur in controlled bursts (max 50MB) with
adaptive intervals to achieve target rates. Applies after initial device
fill.
Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#18093
Free issue threads might block waiting for synchronous DDT, BRT or
GANG header reads. So unlike other taskqs using ZTI_SCALE to scale
with number of CPUs, here we also need some amount of threads to
potentially saturate pool reads. I am not sure we always want the
96 threads we had before ZTI_SCALE introduction at #11966 on small
systems, but lets make it at least 32.
While here, make free taskqs configurable, similar to read and
write ones.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Signed-off-by: Alexander Motin <alexander.motin@TrueNAS.com>
Closes#17903
mod.h only exists to include the platform-specific mod_os.h, so we can
get rid of it and just call the platform header mod.h.
Then, create a libspl mod.h, and move the relevant items to it so we can
start building on it.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17537
