The sysctl is a Unix interface used to modify variables that the kernel uses to determine behavior. There are two ways to work with sysctl: by directly reading and modifying files in /proc/sys and by using the sysctl program supplied with most distributions. The regedit interface is the closest parallel for Windows.
Questions tagged [sysctl]
174 questions
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sysctl: setting key "kernel.softlockup_panic": Invalid argument
When I am trying to set kernel.softlockup_panic value to 30 instead of 0. I am getting Invalid argument error
# sysctl -w kernel.softlockup_panic=30
Error message
# sysctl: setting key "kernel.softlockup_panic": Invalid…
Kanishka Dutta
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What "subbus", "secbus" and "pribus" mean in output of sysctl in FreeBSD
what is the meaning of these terms: "subbus", "secbus" and "pribus"
Here an example of the output:
dev.pcib.3.subbus: 2
dev.pcib.3.secbus: 2
dev.pcib.3.pribus: 0
dev.pcib.3.domain: 0
Does it map to pci address (pci:U:X:Y:Z)?
Why it is not…
AHS
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nginx monitoring failed to load status page under load
Nginx monitoring script so-called ztc failing to load nginx test page (mostly under highest load to nginx about 2000 rps, which used as proxy), causing errors like "nginx is down" on zabbix, and, in a second, everything seems to be OK.
…
d.ansimov
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2 answers
error setting net.ipv4.tcp_tw_reuse & net.ipv4.tcp_tw_recycle in sysctl.conf
I tried setting the following in my /etc/sysctl.conf file to try and help with a MySQL port exhaustion issue:
net.ipv4.tcp_tw_reuse = true
net.ipv4.tcp_tw_recycle = true
But I get an error when running sysctl -p:
sysctl: setting key…
bluethundr
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Mysql start dropping connection when peak hours
Our database start dropping connection during the peak hours. There are about 3% connection dropped and mysql return message "mysqli::mysqli(): (HY000/2003): Can't connect to MySQL server on '10.88.***' (99)" . I have tuned several mysql and kernel…
Chris
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update /etc/sysctl.conf with Python's ConfigParser
I am able to use Python's ConfigParser library to read /etc/sysctl.conf by adding a [dummy] section and overriding ConfigParser's read() method as follows:
class SysctlConfigParser(ConfigParser.ConfigParser):
def read(self, fn):
text =…
user389238
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about the relation between "net.ipv4.tcp_timestamps" and "net.ipv4.tcp_tw_reuse"
when I make performance testing with jmeter,the client reports the error"the request can not reach",I google the error,most of the answers refer to the "net.ipv4.tcp_tw_reuse",set it to 1,but someone say ,if wanna makie it work,must work with…
Yan Lincle
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Is IPv6 send-to-self possible in linux
I am trying to create a setup for testing network equipment, and would like to use multiple (3) NICs in a single PC to produce traffic through an external device, i.e. a network switch. From one interface to another.
All of the tests are for IPv6…
Bill
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Creating BigInsights (IBM Hadoop) Docker image, sysctl issue
I'm trying to create a docker image using IBM BigInsights QuickStart Edition to be run on a DOCKER container cloud (e.g. IBM Bluemix) with the Native Software Installer which can be found…
Romeo Kienzler
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nginx upstream with several redis "Connection timed out" errors
I have nginx with upstream for 4 redis-servers. Sometimes I'm getting such kind of errors (20-30 per minute, only for first & second servers in upstream) in nginx error.log:
... upstream timed out (110: Connection timed out) while connecting to…
d.ansimov
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2 answers
How to execute command before starting every service
I want to set security limits for every service in /etc/init.d say
ulimit -c unlimited
but this should execute while issuing "service start" or "/etc/init.d/ start".
Is there a generic path, so that if we write there it will…
Sasikiran Vaddi
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Enabling core files on CentOS 6
I am trying to enable core files on a machine running CentOS; however, nothing I have tried has produced core files…here is what I have done:
Added the following two lines to /etc/security/limits.conf:
* hard core unlimited
* soft …
Kabb5
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Reading dynamically created file inside /proc/sys
LKM can create dynamically entries inside /proc/sys, but sysctl (not the Linux command but C's sysctl) accepts as first argument an array of ints with predefined values representing entries inside /proc/sys. My question is: can I read a dynamically…
alexandernst
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How to get iOS CPU Core usage?
There has been a lot of the same question, but yet I cannot find great answers. I've looked at codes from this particular post which gives me usage per core, but it is inaccurate, always stuck at 14% or so even when Instrument tells me one core is…
Shane Hsu
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How do I read buffer data retrieved from sysctlbyname() in iPhone?
I'm trying to get TCP open port list in iphone by using sysctlbyname().
sysctlbyname(const char *name, void *oldp, size_t *oldlenp, void *newp,
size_t newlen);
.
#include
size_t len = 0;
if…
virata
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