Today we discuss some small adjustments to make to a NetBSD default config in order to increase performance on desktop targets

kernel config

# set max number of allowed processes to 1044
maxusers        64
# Alternate buffer queue strategies for better responsiveness under high
# disk I/O load.
options 	BUFQ_READPRIO
options 	BUFQ_PRIOCSCAN

resource limits

Add this to your /etc/login.conf in order to increase 'capabilities' (=loosen session resource limits) for the 'default' login class (hence every user), system-wide:

default:\
    :path=/usr/bin /bin /usr/sbin /sbin /usr/X11R6/bin /usr/pkg/bin /usr/pkg/sbin /usr/local/bin:\
    :umask=022:\
    :datasize-max=3072M:\
    :datasize-cur=1024M:\
    :maxproc-max=1044:\
    :maxproc-cur=1024:\
    :openfiles-cur=512:\
    :stacksize-cur=16M:
    :copyright=/dev/null:

kernel state tunables

Set those sysctl(7) values permanently at boot time but adding what follows to your /etc/sysctl.conf

# 128M PAGE_SIZE 
kern.ipc.shmmaxpgs=32768
# increase max number of file descriptors
kern.maxfiles=1772

# automatic network buffers resize
net.inet.tcp.recvbuf_auto=1
net.inet.tcp.sendbuf_auto=1
# 16MB buffers upper limit
net.inet.tcp.sendbuf_max=16777216 
net.inet.tcp.recvbuf_max=16777216
net.inet.ip.ifq.maxlen = 4096

FFSv2 WAPBL

WAPBL provides data journaling on NetBSD for the FFSv{1,2} filesystems .
Journaling improves writing performance noticeably by reducing synchronization, especially when creating a large number of inodes. It also avoids having to go through a thorough file-systems check during a crash recovery , speeding up boot time significantly in those cases

Enabling WAPBL on NetBSD is as easy as appending 'log' to FS mount options for each FFSv{1,2} partition found in /etc/fstab:

/dev/wd0a		/	        ffs	rw,log		 1 1
/dev/wd0e		/usr	        ffs	rw,log		 1 2
/dev/wd0f		/var	        ffs	rw,log		 1 2
/dev/wd0g	        /home	        ffs	rw,log		 1 2

tmpfs

mount a tmpfs disk on directories with a high r/w turnover so as to decrease access time and increase maximum throughput, by adding suitable entries to /etc/fstab

tmpfs		/tmp		tmpfs	rw,-m=1777,-s=4295467008
tmpfs		/var/shm	tmpfs	rw,-m1777,-sram%25
tmpfs		/var/tmp	tmpfs	rw,-m1777,-sram%25

optimized CC FLAGS and pkgsrc options

Use devel/cpuflags to determine the best compiler flags to set for your CPU;
Now you can specify them inside your /etc/mk.conf

PKGSRC_COMPILER?= gcc
CFLAGS+=	-O2 -mfpmath=sse -msse3 -march=x86-64
CPUFLAGS+=       -mfpmath=sse -msse3 -march=x86-64
COPTS+=         -O2
MAKE_JOBS=	3
GZIP?=	        --fast

# TIPS :

Add swap space to a running system

 %  dd if=/dev/zero bs=1M count=128 of=<FS>/swap
 % chmod 600 <FS>/swap
 % swapctl -a -p 1 <FS>/swap

Providing file-based swap is slower than a swap partition, giving the additional swap space a priority of 1 (through '-p 1', least is a value of '0' ) forces it be relied upon for paging only when the swap partition has been used up.

check for memory in use

using top(1)
```
  % top -n 1 | head -n 5 | tail -n 2
  Memory: 665M Act, 74M Inact, 14M Wired, 113M Exec, 119M File, 3045M Free
  Swap: 6144M Total, 6144M Free
  
```
using sysutils/free
```
% free -m

     total       used       free    buffers
Mem:          3923        885       3037        232
Swap:         6144          0       6144
```
- reading /proc/meminfo
```
% cat /proc/meminfo

    total:    used:    free:  shared: buffers: cached:
Mem:  4113620992 925655040 3187965952        0 126500864 794152960
Swap: 6442938368        0 6442938368
MemTotal:   4017208 kB
MemFree:    3113248 kB
MemShared:        0 kB
Buffers:     123536 kB
Cached:      775540 kB
SwapTotal:  6291932 kB
SwapFree:   6291932 kB
```
To get a percentage of free memory:
```
% cat /proc/meminfo | awk 'FNR== 2 {print $3/$2 *100}'
```
suckless performance monitor

I use good old XOSview: