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howtos:sysctl [d/m/Y H:i] (current)
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 +<​file>​
 +# 256 KB default performs well experimentally,​ and is often recommended by ISVs.
 +net.core.rmem_default = 262144
 +net.core.wmem_default = 262144
  
 +# When opening a high-bandwidth connection while the receiving end is under
 +# memory pressure, disk I/O may be necessary to free memory for the socket,
 +# making disk latency the effective latency for the bandwidth-delay product
 +# initially. ​ For 10 Gb ethernet and SCSI, the BDP is about 5 MB.  Allow 8 MB
 +# to account for overhead, to ensure that new sockets can saturate the medium
 +# quickly.
 +net.core.rmem_max = 8388608
 +net.core.wmem_max = 8388608
 +
 +# Allow a deep backlog for 10 Gb and bonded Gb ethernet connections
 +net.core.netdev_max_backlog = 10000
 +
 +# Always have one page available, plus an extra for overhead, to ensure TCP NFS
 +# pageout doesn'​t stall under memory pressure. ​ Default to max unscaled window,
 +# plus overhead for rmem, since most LAN sockets won't need to scale.
 +net.ipv4.tcp_rmem = 8192 87380 8388608
 +net.ipv4.tcp_wmem = 8192 65536 8388608
 +
 +# Always have enough memory available on a UDP socket for an 8k NFS request,
 +# plus overhead, to prevent NFS stalling under memory pressure. ​ 16k is still
 +# low enough that memory fragmentation is unlikely to cause problems.
 +net.ipv4.udp_rmem_min = 16384
 +net.ipv4.udp_wmem_min = 16384
 +
 +# Ensure there'​s enough memory to actually allocate those massive buffers to a
 +# socket.
 +net.ipv4.tcp_mem = 8388608 12582912 16777216
 +net.ipv4.udp_mem = 8388608 12582912 16777216
 +</​file>​
howtos/sysctl.txt · Last modified: d/m/Y H:i (external edit)