Questions tagged [kernel]
In computing, the kernel is the main component of most computer operating systems; it is a bridge between applications and the actual data processing done at the hardware level. The kernel's responsibilities include managing the system's resources (the communication between hardware and software components).
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rm on a directory with millions of files
Background: physical server, about two years old, 7200-RPM SATA drives connected to a 3Ware RAID card, ext3 FS mounted noatime and data=ordered, not under crazy load, kernel 2.6.18-92.1.22.el5, uptime ...
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How does vm.overcommit_memory work?
When I use the default settings:
vm.overcommit_memory = 0
vm.overcommit_ratio = 50
I can read these values from /proc/meminfo file:
CommitLimit: 2609604 kB
Committed_AS: 1579976 kB
But when I ...
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Turn off the Linux OOM killer by default?
The OOM killer on Linux wreaks havoc with various applications every so often, and it appears that not much is really done on the kernel development side to improve this. Would it not be better, as a ...
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Best way to disable swap in Linux
I am running a custom compiled 3.18.9 kernel and I am wondering about the best way to disable swap on the system. I also use init if it makes a difference.
Is it enough to comment or remove the swap ...
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Soft limit vs Hard limit?
Can anyone explain in layman's terms what the difference between soft and hard limit is?
Should I set my soft and hard limit to be the same? Or should soft be significantly lower? Does the system ...
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How do I check what kernel options were compiled without looking at /boot/config-*
How do I check what options are compiled into a Linux kernel without looking at /boot/config-* and if I don't have access to the /boot/config-* file that's left over?
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How do ulimit -n and /proc/sys/fs/file-max differ?
I notice that on a new CentOS image that I just booted up off of EC2 that the ulimit default is 1024 open files, but /proc/sys/fs/file-max is set at 761,408 and I'm wondering how these two limits work ...
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Disabling rp_filter on one interface
I have an Ubuntu 16.04 Server which is acting as a router with multiple (VLAN) interfaces. By default, rp_filter (reverse path filtering) is enabled for all interfaces. I want to keep it that way, but ...
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Why is Linux choosing the wrong source ip address
and what to do to let it choose the right one?
This all happens inside an OpenVZ container:
The Host is Debian/Wheezy with Redhat/OpenVZ Kernel:
root@mycl2:~# uname -a
Linux mycl2 2.6.32-openvz-...
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Reloading a kernel "live" in CentOS / RHEL 6
When upgrading the kernel package on CentOS or RHEL 6, is it possible to load the new kernel without rebooting?
My gut tells me it's not, but if it were, it'd be handy - especially when compiling ...
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Disable ICMP Unreachable replies
I am using a Debian 6 - 64bit OS and my server is ddosed/flooded through udp protocol from time to time. I basically host game-servers and my firewall is set to rate-limit the packets on allowed ports ...
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How do i view / enable kernel logs on an ec2 instance (amazon linux)?
I've got a amazon ec2 server that i'm playing around with TCP settings in the sysctl.conf to increase the number of concurrent TCP connections it can handle, and i want to be able to view the kernel ...
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Kernel update without reboot [duplicate]
Possible Duplicate:
Reloading a kernel “live” in CentOS / RHEL 6
How can i update kernel on Centos without reboot .?
I found ksplice but it is not supported for Centos.
Regards,
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overriding default scheduler for blkio requests in cgroups
I am trying to optimize a set of servers that have to reside on single machine. i.e. i can have multiple application server, a DB server and of course a samba server as well in same instance. Now I ...
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Under what circumstances will Linux ignore the route table when choosing the MAC address for an outbound frame?
While debugging a problem with the networking configuration for a set of virtual machines running under KVM, I discovered a circumstance where the kernel in the guest VM has decided to stamp the ...
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