====== PI Berechnen ======

PI Berechnung auf 5000 Kommastellen.
Dies lastet jedoch nur einen Core aus.

<code>
time echo "scale=5000; a(1)*4" | bc -l
</code>

----

**Ergebnisse:**

^ Hardware               ^ CPU                        ^ Zeit      ^
| Selfmade Bender        | AMD x3 415e @ 2,5Ghz       | 37 Sec    |
| Selfmade bastardo      | Via C6 @ 530Mhz            | 213 Sec   |
| Dell Workstation       | Intel P4 @ 3Ghz            | 53 Sec    |
| Lenovo X390            | Intel i5-8265U @ 1,6Ghz    | 16 Sec    |
| HP DL380 G8            | Intel Xeon E5-2620 @ 2Ghz  | 28 Sec    |
| Dell R7525             | AMD Epyc 7452 @ 3,35Ghz    | 16 Sec    |
| Raspberry Zero         | ARMv6 rev7 @ 700Mhz        | 146 Sec   |
| Raspberry Pi 1         | ???                        | 196 Sec   |
| Raspberry Pi 3         | ???                        | 67 Sec    |
| Raspberry Pi 4         | ARMv7 rev3 @ 2Ghz (OC)     | 37 Sec    |

  * Server bender 3x CPU AMD X3 415e @ 2,50Ghz: 37,5 Sec
  * Server bastardo 1x CPU VIA C6 (Nehemiah) @ 532Mhz: 213 Sec
  * Workstation trojar 1x CPU P4 @ 3Ghz: 53,9 Sec
  * Lenovo X390 i5-8265U CPU @ 1.60GHz: 16,5 Sec
  * HP DL380 G8 Xeon CPU E5-2620 0 @ 2.00GHz: 28 Sec
  * Dell R7525 AMD EPYC 7452 32-Core: 16 Sec
  * Raspberry 1: 3m 47 Sec
  * Raspberry 3: 1m 16 Sec
  * Raspberry 4: 37 Sec


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----

<code>
time echo "scale=10000; a(1)*4" | bc -l
</code>

----

**Ergebnisse:**

^ Hardware               ^ CPU                        ^ Zeit      ^
| Lenovo T460s           | Intel i7-6600U             | 37 Sec    |
| Lenovo X390            | Intel i5-8265U @ 1,6Ghz    | 94 Sec    |
| HP DL380 G8            | Intel Xeon E5-2620 @ 2Ghz  | 168 Sec   |
| HP Microsurf G10       | AMD Opteron X3431 | 2,10Ghz| 157 Sec   |
| Dell R7525             | AMD Epyc 7452 @ 3,35Ghz    | 96 Sec    |

\\
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PI Multi Start
<code>
for i in $(seq <cpucores>)  ; do echo "scale=5000; a(1)*4" | bc -l & done

Beispiel für 32 Cores:
for i in $(seq 32)  ; do echo "scale=5000; a(1)*4" | bc -l & done
</code>