Added environment docs (#555)

* Create ENVIRONMENT.md

* More intel added

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+# Environment
+This file just contains some intel about the environment in use and what has been done to get it into that state.
+
+## Machine Type
+
+* Hetzner AX161, Dedicated Hosted Hardware
+* CPU: AMD EPYC 7502P 32 cores / 64 threads @ 2.5 GHz
+* Memory: 128 GB ECC DDR4 RAM
+* 2x SAMSUNG MZQL2960HCJR-00A07, 1 TB, Software RAID-1
+* CentOS 9, Linux 5.14.0-378.el9.x86_64
+
+## Configuration
+
+* SMT off
+* Turbo Boost Off
+* Filesystem EXT4 
+
+## Details
+
+### CPU
+``` 
+$ cat /proc/cpuinfo 
+processor	: 0
+vendor_id	: AuthenticAMD
+cpu family	: 23
+model		: 49
+model name	: AMD EPYC 7502P 32-Core Processor
+stepping	: 0
+microcode	: 0x8301055
+cpu MHz		: 2500.000
+cache size	: 512 KB
+physical id	: 0
+siblings	: 32
+core id		: 0
+cpu cores	: 32
+apicid		: 0
+initial apicid	: 0
+fpu		: yes
+fpu_exception	: yes
+cpuid level	: 16
+wp		: yes
+flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf rapl pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate ssbd mba ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbnoinvd arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif v_spec_ctrl umip rdpid overflow_recov succor smca sme sev sev_es
+bugs		: sysret_ss_attrs spectre_v1 spectre_v2 spec_store_bypass retbleed smt_rsb
+bogomips	: 4990.70
+TLB size	: 3072 4K pages
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 43 bits physical, 48 bits virtual
+power management: ts ttp tm hwpstate cpb eff_freq_ro [13] [14]
+... more for all other cores
+```
+
+## Setup
+
+### Turn SMT off
+Disable during boot via boot-param, able to switch it on later again, if needed.
+
+Add `nosmt` to grub boot config in `/etc/default/grub` 
+
+```
+# Added nosmt to command line
+GRUB_CMDLINE_LINUX="biosdevname=0 crashkernel=auto rd.auto=1 consoleblank=0 nosmt"
+```
+
+Update boot config:
+``` 
+sudo grub2-mkconfig -o /boot/grub2/grub.cfg
+```
+
+### Turbo Off
+Using the legacy `/etc/rc.local` concept to change things during boot:
+
+```
+# Turn SMT off via software as well, already got nosmt in grub
+echo off >  /sys/devices/system/cpu/smt/control
+
+# Turn off turbo boost
+echo 0 |tee /sys/devices/system/cpu/cpufreq/boost
+```
+### Reduce Swapping
+Reduce from default 60 to 10% memory pressure by adding `vm.swappiness = 10` to `/etc/sysctl.conf`.
+
+## Verify
+Check after boot if all settings have been applied. Can also be used to control these during runtime.
+
+* SMT off: `cat /sys/devices/system/cpu/smt/active` must be 0
+* SWAP: `cat /proc/sys/vm/swappiness` must be 10
+* Turbo off: `cat /sys/devices/system/cpu/cpufreq/boost` must be 0
+
+
+
+