#Custom by V
# /etc/sysctl.d/90-ceph.conf
# generic kernel tunings for ceph (w/ Kernel > 3.5)

# minimal amount of swapping but not entirely disabling it
vm.swappiness = 1

# allow more simultanous tcp socket creations (defaults to a very low 128)
# in-/decrease both values identical
net.core.somaxconn = 2048
net.ipv4.tcp_max_syn_backlog = 30000

## Maximum number of remembered connection requests, default is 128
net.core.netdev_max_backlog = 300000

# For more information, see sysctl.conf(5) and sysctl.d(5).
# 10GB/54MB (56623104)
net.core.rmem_max = 56623104
net.core.wmem_max = 56623104
net.core.rmem_default = 56623104
net.core.wmem_default = 56623104
net.core.optmem_max = 40960
net.ipv4.tcp_rmem = 4096 87380 56623104
net.ipv4.tcp_wmem = 4096 65536 56623104

## Decrease TIME_WAIT seconds, default is 30 seconds
net.ipv4.tcp_fin_timeout = 10

## Maximum number of remembered connection requests, default is 128
net.ipv4.tcp_max_syn_backlog = 50000

## Increase the tcp-time-wait buckets pool size to prevent simple DOS attacks, default is 8192
net.ipv4.tcp_max_tw_buckets = 2000000

## Tells the system whether it should start at the default window size only for TCP connections
## that have been idle for too long, default is 1
net.ipv4.tcp_slow_start_after_idle = 0

net.ipv4.tcp_syncookies = 0

# Recycle and Reuse TIME_WAIT sockets faster, default is 0 for both
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1

# >= luminous and various OS. If not already set by the OS (might be obsolete, but doesn't harm)
fs.aio-max-nr = 1048576

# broader port range
#net.ipv4.ip_local_port_range = 8192 65535

# consumes some kb more RAM but necessary for aggregation of
#    highly threaded applications on a host (e.g. ceph-host or mid- to huge-sized container-host)
net.ipv4.tcp_max_tw_buckets = 1048576
kernel.pid_max = 4194303

##
## Following values for 10GE / aggregated 2x10GE
#
# allow testing with buffers up to 64MB 
##net.core.rmem_max = 67108864 
##net.core.wmem_max = 67108864 
# increase Linux autotuning TCP buffer limit to 32MB
##net.ipv4.tcp_rmem = 4096 87380 33554432
##net.ipv4.tcp_wmem = 4096 65536 33554432
# recommended default congestion control is htcp 
##net.ipv4.tcp_congestion_control=htcp
# recommended for CentOS7/Debian8 hosts
##net.core.default_qdisc = fq_codel

# recommended for hosts with jumbo frames enabled (only If)
# net.ipv4.tcp_mtu_probing=1

#If your servers talk UDP, also up these limits, default is 4096
net.ipv4.udp_rmem_min = 8192
net.ipv4.udp_wmem_min = 8192


## Disable source redirects
## Default is 1
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.all.accept_redirects = 0

## Disable source routing, default is 0
net.ipv4.conf.all.accept_source_route = 0