Re: measuring swap partition speed

From: Mark Millard <marklmi_at_yahoo.com>
Date: Thu, 21 Dec 2023 03:48:14 UTC 
Just an example for comparison/contrast:

8 GiBYte RPi4B "C0T" SOC
USB3 SSD boot media (no other media)

# uname -apKU
FreeBSD generic 14.0-STABLE FreeBSD 14.0-STABLE #0 stable/14-n266002-2ef9079ece5a: Sat Dec 16 08:49:23 UTC 2023     root@releng1.nyi.freebsd.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC arm64 aarch64 1400501 1400501

(So, FreeBSD-14.0-STABLE-arm64-aarch64-RPI-20231216-2ef9079ece5a-266002.img based.)

# more /boot/efi/config.txt 
[all]
arm_64bit=1
dtparam=audio=on,i2c_arm=on,spi=on
dtoverlay=mmc
dtoverlay=disable-bt
device_tree_address=0x4000
kernel=u-boot.bin

[pi4]
hdmi_safe=1
armstub=armstub8-gic.bin
# My additions:
over_voltage=6
sdram_freq_min=3200
arm_freq_min=2000
force_turbo=1


# gpart show -p
=>       63  468862065    da0  MBR  (224G)
         63       1985         - free -  (993K)
       2048     102400  da0s1  fat32lba  [active]  (50M)
     104448  468757680  da0s2  freebsd  (224G)

=>        0  468757680   da0s2  BSD  (224G)
          0        128          - free -  (64K)
        128  451979136  da0s2a  freebsd-ufs  (216G)
  451979264   16777216  da0s2b  freebsd-swap  (8.0G)
  468756480       1200          - free -  (600K)

# more /boot/loader.conf
# Configure USB OTG; see usb_template(4).
hw.usb.template=3
umodem_load="YES"
# Multiple console (serial+efi gop) enabled.
boot_multicons="YES"
boot_serial="YES"
# Disable the beastie menu and color
beastie_disable="YES"
loader_color="NO"

# swapoff /dev/label/growfs_swap
# dd if=/dev/urandom of=/dev/da0s2b bs=8k count=250000 conv=sync status=progress
^C478830592 bytes (479 MB, 457 MiB) transferred 22.001s, 22 MB/s
60557+0 records in
60556+0 records out
496074752 bytes transferred in 22.790754 secs (21766491 bytes/sec)

Adding:

vm.pageout_oom_seq=120
vm.pfault_oom_attempts=-1

to /boot/loader.config gets the same sort of result:

# more /boot/loader.conf
# Configure USB OTG; see usb_template(4).
hw.usb.template=3
umodem_load="YES"
# Multiple console (serial+efi gop) enabled.
boot_multicons="YES"
boot_serial="YES"
# Disable the beastie menu and color
beastie_disable="YES"
loader_color="NO"
#
vm.pageout_oom_seq=120
vm.pfault_oom_attempts=-1

# swapoff /dev/label/growfs_swap
# dd if=/dev/urandom of=/dev/da0s2b bs=8k count=250000 conv=sync status=progress
^C1085161472 bytes (1085 MB, 1035 MiB) transferred 50.000s, 22 MB/s
134642+0 records in
134641+0 records out
1102979072 bytes transferred in 50.816711 secs (21705046 bytes/sec)


===
Mark Millard
marklmi at yahoo.com