X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=Documentation%2Ffilesystems%2Fproc.txt;h=72af5de1effb44a93d907ed4e0117ec403a8257e;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=944cf109a6f5a36ad51cf6d8fd47819ab220986e;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 944cf109a..72af5de1e 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -39,6 +39,8 @@ Table of Contents 2.9 Appletalk 2.10 IPX 2.11 /proc/sys/fs/mqueue - POSIX message queues filesystem + 2.12 /proc//oom_adj - Adjust the oom-killer score + 2.13 /proc//oom_score - Display current oom-killer score ------------------------------------------------------------------------------ Preface @@ -121,7 +123,7 @@ Table 1-1: Process specific entries in /proc .............................................................................. File Content cmdline Command line arguments - cpu Current and last cpu in wich it was executed (2.4)(smp) + cpu Current and last cpu in which it was executed (2.4)(smp) cwd Link to the current working directory environ Values of environment variables exe Link to the executable of this process @@ -309,13 +311,13 @@ is the same by default: > cat /proc/irq/0/smp_affinity ffffffff -It's a bitmask, in wich you can specify wich CPUs can handle the IRQ, you can +It's a bitmask, in which you can specify which CPUs can handle the IRQ, you can set it by doing: > echo 1 > /proc/irq/prof_cpu_mask This means that only the first CPU will handle the IRQ, but you can also echo 5 -wich means that only the first and fourth CPU can handle the IRQ. +which means that only the first and fourth CPU can handle the IRQ. The way IRQs are routed is handled by the IO-APIC, and it's Round Robin between all the CPUs which are allowed to handle it. As usual the kernel has @@ -408,7 +410,7 @@ VmallocChunk: 111088 kB this memory, making it slower to access than lowmem. LowTotal: LowFree: Lowmem is memory which can be used for everything that - highmem can be used for, but it is also availble for the + highmem can be used for, but it is also available for the kernel's use for its own data structures. Among many other things, it is where everything from the Slab is allocated. Bad things happen when you're out of lowmem. @@ -1124,11 +1126,15 @@ debugging information is displayed on console. NMI switch that most IA32 servers have fires unknown NMI up, for example. If a system hangs up, try pressing the NMI switch. -[NOTE] - This function and oprofile share a NMI callback. Therefore this function - cannot be enabled when oprofile is activated. - And NMI watchdog will be disabled when the value in this file is set to - non-zero. +nmi_watchdog +------------ + +Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero +the NMI watchdog is enabled and will continuously test all online cpus to +determine whether or not they are still functioning properly. + +Because the NMI watchdog shares registers with oprofile, by disabling the NMI +watchdog, oprofile may have more registers to utilize. 2.4 /proc/sys/vm - The virtual memory subsystem @@ -1214,9 +1220,9 @@ applications are using mlock(), or if you are running with no swap then you probably should increase the lower_zone_protection setting. The units of this tunable are fairly vague. It is approximately equal -to "megabytes". So setting lower_zone_protection=100 will protect around 100 +to "megabytes," so setting lower_zone_protection=100 will protect around 100 megabytes of the lowmem zone from user allocations. It will also make -those 100 megabytes unavaliable for use by applications and by +those 100 megabytes unavailable for use by applications and by pagecache, so there is a cost. The effects of this tunable may be observed by monitoring @@ -1249,7 +1255,7 @@ to allocate (but not use) more memory than is actually available. address space are refused. Used for a typical system. It ensures a seriously wild allocation fails while allowing overcommit to reduce swap usage. root is allowed to - allocate slighly more memory in this mode. This is the + allocate slightly more memory in this mode. This is the default. 1 - Always overcommit. Appropriate for some scientific @@ -1532,10 +1538,10 @@ TCP settings tcp_ecn ------- -This file controls the use of the ECN bit in the IPv4 headers, this is a new +This file controls the use of the ECN bit in the IPv4 headers. This is a new feature about Explicit Congestion Notification, but some routers and firewalls -block trafic that has this bit set, so it could be necessary to echo 0 to -/proc/sys/net/ipv4/tcp_ecn, if you want to talk to this sites. For more info +block traffic that has this bit set, so it could be necessary to echo 0 to +/proc/sys/net/ipv4/tcp_ecn if you want to talk to these sites. For more info you could read RFC2481. tcp_retrans_collapse @@ -1582,7 +1588,7 @@ Enable the strict RFC793 interpretation of the TCP urgent pointer field. The default is to use the BSD compatible interpretation of the urgent pointer pointing to the first byte after the urgent data. The RFC793 interpretation is to have it point to the last byte of urgent data. Enabling this option may -lead to interoperatibility problems. Disabled by default. +lead to interoperability problems. Disabled by default. tcp_syncookies -------------- @@ -1727,7 +1733,7 @@ error_burst and error_cost These parameters are used to limit how many ICMP destination unreachable to send from the host in question. ICMP destination unreachable messages are -sent when we can not reach the next hop, while trying to transmit a packet. +sent when we cannot reach the next hop while trying to transmit a packet. It will also print some error messages to kernel logs if someone is ignoring our ICMP redirects. The higher the error_cost factor is, the fewer destination unreachable and error messages will be let through. Error_burst @@ -1851,7 +1857,7 @@ proxy_qlen Maximum queue length of the delayed proxy arp timer. (see proxy_delay). -app_solcit +app_solicit ---------- Determines the number of requests to send to the user level ARP daemon. Use 0 @@ -1958,6 +1964,22 @@ a queue must be less or equal then msg_max. maximum message size value (it is every message queue's attribute set during its creation). +2.12 /proc//oom_adj - Adjust the oom-killer score +------------------------------------------------------ + +This file can be used to adjust the score used to select which processes +should be killed in an out-of-memory situation. Giving it a high score will +increase the likelihood of this process being killed by the oom-killer. Valid +values are in the range -16 to +15, plus the special value -17, which disables +oom-killing altogether for this process. + +2.13 /proc//oom_score - Display current oom-killer score +------------------------------------------------------------- + +------------------------------------------------------------------------------ +This file can be used to check the current score used by the oom-killer is for +any given . Use it together with /proc//oom_adj to tune which +process should be killed in an out-of-memory situation. ------------------------------------------------------------------------------ Summary