Difference between revisions of "Data accumulation rate"
From MCEWiki
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− | |+ 48HP subrack data accumulation rate in Gigabytes (<math>10^9</math> bytes) per hour | + | |+ 48HP subrack data accumulation rate in Gigabytes (<math>10^9</math> bytes) per hour |
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! | ! | ||
+ | ! 100 Hz | ||
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! 200 Hz | ! 200 Hz | ||
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+ | | 0.55 | ||
| 0.8 | | 0.8 | ||
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+ | | 0.7 | ||
| 1.1 | | 1.1 | ||
| 1.4 | | 1.4 | ||
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{| class="wikitable" | {| class="wikitable" | ||
− | |+ 48HP subrack data accumulation rate in Gigabytes (<math>10^9</math> bytes) per day | + | |+ 48HP subrack data accumulation rate in Gigabytes (<math>10^9</math> bytes) per day |
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! | ! | ||
+ | ! 100 Hz | ||
! 150 Hz | ! 150 Hz | ||
! 200 Hz | ! 200 Hz | ||
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! 25 rows | ! 25 rows | ||
+ | | 12.9 | ||
| 19.3 | | 19.3 | ||
| 25.7 | | 25.7 | ||
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! 33 rows | ! 33 rows | ||
+ | | 17.0 | ||
| 25.5 | | 25.5 | ||
| 34.0 | | 34.0 | ||
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! 41 rows | ! 41 rows | ||
+ | | 21.1 | ||
| 31.7 | | 31.7 | ||
| 42.2 | | 42.2 |
Revision as of 12:54, 22 June 2013
This page gives some rules for estimating the accumulation rate of data on disk for a running MCE.
In general, during a regular acquisition, the data rate of an MCE is:
- <math>S_w \times N_c \times N_r \times R</math>
where:
- <math>S_w</math> is the word size (=32 bits)
- <math>N_c</math> is the number of columns read (<math>=8 \times N_{RC}</math>, where <math>N_{RC}</math> is the number of readout cards used)
- <math>N_r</math> is the number of rows read
- <math>R</math> is the read-out data rate
A useful approximation is:
- a single readout card reading 41 rows at 400 Hz is <math>\approx0.5</math> megabytes/second.
Here's are some tables of accumulation rates for a two readout card 48HP subrack (multiply by 2 for a full sized 72HP subrack with 4 readout cards) for various data rates and numbers of rows:
100 Hz | 150 Hz | 200 Hz | 300 Hz | 400 Hz | 600 Hz | |
---|---|---|---|---|---|---|
25 rows | 0.55 | 0.8 | 1.1 | 1.6 | 2.1 | 3.2 |
33 rows | 0.7 | 1.1 | 1.4 | 2.1 | 2.8 | 4.2 |
41 rows | 0.9 | 1.3 | 1.8 | 2.6 | 3.5 | 5.3 |
100 Hz | 150 Hz | 200 Hz | 300 Hz | 400 Hz | 600 Hz | |
---|---|---|---|---|---|---|
25 rows | 12.9 | 19.3 | 25.7 | 38.6 | 51.5 | 77.2 |
33 rows | 17.0 | 25.5 | 34.0 | 51.0 | 68.0 | 102.0 |
41 rows | 21.1 | 31.7 | 42.2 | 63.3 | 84.5 | 126.7 |