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Showing posts from May, 2020

[Quick Note] Failed to install pywinrm on CentOS 8

You may see error message " Running install for pykerberos … error " when install pywinrm on CentOS 8. The additional errors are " unable to execute 'gcc': No such file or directory " and " command 'gcc' failed with exit status 1 ". The reason because gcc dependence is missing on the machine. You need to run following command to install gcc then try install pywinrm again. # yum install gcc

Balanced Memory Configuration for ESXi Servers

Background ESXi servers are fundamental infrastructure. The underly hardware performance has a butterfly effect on the upper layer virtual machines and applications. Since there is less than 10% performance overhead on the virtualization layer. So it's valuable to get full performance on the hardware layer. Memory is a big player in hardware performance tuning. Balanced memory configuration is very important. I wrote an article " LRDIMM or RDIMM on ESXi hosts? " a long time ago. It was the understanding in 2016. I did some research recently. I hope the following study help with your hardware decisions. This study is based on Intel Xeon 2 nd Generation Scalable Processors. 1. Basic Concepts Before we talk about balanced memory and optimized memory. Let's take a look at some basic concepts which will be used in the article. 1.1 Memory Channel The memory channels control reading and writing bandwidth operations between the CPU and memory modules. Think about it like the