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@motorailgun
motorailgun / idea.md
Last active June 18, 2024 06:22
Installing Windows and Linux into the same partition

Installing Windows and Linux into the same partition

But WHY?

There was a reddit post about installing Arch on NTFS3 partition. Since Windows and Linux doesn't have directories with same names under the /(C:\), I thought it's possible, and turned out it was actually possible.
If you are not familiar to Linux, for example you've searched on Google "how to dualboot Linux and Windos" or brbrbr... you mustn't try this. This is not practical.

Pre-requirements

  • UEFI system
  • Any Linux live-boot CD/DVD/USB... with Linux kernel newer than 5.15
  • Windows installer USB
@mrpeardotnet
mrpeardotnet / PVE-HP-ssacli-smart-storage-admin.md
Created November 25, 2019 22:10
HP Smart Storage Admin CLI (ssacli) installation and usage on Proxmox PVE (6.x)

HP Smart Storage Admin CLI (ssacli) installation and usage on Proxmox PVE (6.x)

Why use HP Smart Storage Admin CLI?

You can use ssacli (smart storage administrator command line interface) tool to manage any of supported HP Smart Array Controllers in your Proxmox host without need to reboot your server to access Smart Storage Administrator in BIOS. That means no host downtime when managing your storage.

CLI is not as convenient as GUI interface provided by BIOS or desktop utilities, but still allows you to fully manage your controller, physical disks and logical drives on the fly with no Proxmox host downtime.

ssacli replaces older hpssacli, but shares the same syntax and adds support for newer servers and controllers.

Installation

@mohanpedala
mohanpedala / bash_strict_mode.md
Last active June 29, 2024 04:08
set -e, -u, -o, -x pipefail explanation
@plepe
plepe / gist:52ecc9f18efb32c68d18
Last active June 6, 2024 22:23
MDADM and LVM cheat sheet

mdadm

Glossary:

  • md: multiple devices
command description
cat /proc/mdstat show status of all raids
mdadm --detail /dev/md0 detailed status of raid md0
@denji
denji / nginx-tuning.md
Last active June 27, 2024 04:48
NGINX tuning for best performance

Moved to git repository: https://github.com/denji/nginx-tuning

NGINX Tuning For Best Performance

For this configuration you can use web server you like, i decided, because i work mostly with it to use nginx.

Generally, properly configured nginx can handle up to 400K to 500K requests per second (clustered), most what i saw is 50K to 80K (non-clustered) requests per second and 30% CPU load, course, this was 2 x Intel Xeon with HyperThreading enabled, but it can work without problem on slower machines.

You must understand that this config is used in testing environment and not in production so you will need to find a way to implement most of those features best possible for your servers.

@DavidWittman
DavidWittman / iptables-nat.md
Created September 29, 2012 20:38
iptables n'at

iptables n'at

Source NAT

Source NAT changes the source address in IP header of a packet. It may also change the source port in the TCP/UDP headers. The typical usage is to change the a private (rfc1918) address/port into a public address/port for packets leaving your network. Available only in the POSTROUTING chain in iptables.

Syntax

iptables -t nat -A POSTROUTING -i eth1 -j SNAT --to-source 1.2.3.4[:port]

Example

@jboner
jboner / latency.txt
Last active June 29, 2024 19:54
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD