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Data Throughput

These two formulas estimate data throughputs:

Formula 1 (for MP3 only):
MP3 bitrate * Ports / 8 = KB/sec
Or 32kbps * Ports / 8 =KB/sec if MP3 is 32kbps

Formula 2 (for MP3 + wav):
(MP3 bitrate + WAV bitrate) * Ports / 8 = KB/sec
Or (32 kbps + 128 kpbs) * Ports / 8 = 160 kbps / 8 = KB/sec if 32kpbs MP3 + wav

Six VM configurations, with SSD as the cache folder for MCP recording, produced the following measurements from testing for test SW Profile 1 (MP3 32 kbps only):

Table: Data Throughputs for MP3 32 kbps only

Ports Overall Disk (kbps) SSD Drive Disk (kbps)
Total Reads Writes Total Reads Writes
120 554.10 0.12 553.98 536.98 0.00 536.98
240 1075.70 0.50 1075.19 1053.19 0.00 1053.19
300 1332.61 0.06 1332.55 1308.69 0.00 1308.69
360 1601.09 0.00 1601.09 1575.02 0.00 1575.02
420 1847.91 0.00 1847.91 1822.30 0.00 1822.30
480 2109.57 0.00 2109.57 2082.49 0.00 2082.49
540 2461.25 0.00 2461.25 2434.04 0.00 2434.04
600 2728.83 0.00 2728.83 2702.57 0.00 2702.57
660 3010.07 0.00 3010.07 2982.84 0.00 2982.84
720 3310.64 0.00 3310.64 3280.45 0.00 3280.45

Apply Formula 1 to the 120-port and 600-port samples from the table above to achieve these results:

32 kpbs * 120 / 8 = 480 kb close to 534 in the table (in SSD)
32 kpbs * 600 / 8 = 2400 kb close to 2703 in the table (in SSD)

The measurements from real testing are slightly higher than calculations. Because other files such as metadata and JSON files are saved in the same cache folder, the formula might need adjusting.


Below is the table from testing measurement for SW Profile 2 (MP3 + wav) on the same 6 VM configuration with SSD as cache folder of MCP recording:

Table: Data Throughputs for MP3 32 kbps + wav

Ports Overall Disk (kbps) SSD Drive Disk (kbps)
Total Reads Writes Total Reads Writes
120 2444.255 0.25 2444.01 2427.025 0.000 2427.025
240 4881.163 0.01 4881.15 4859.951 0.000 4859.951
300 6083.649 0.00 6083.64 6058.294 0.000 6058.294
360 7380.491 0.00 7380.49 7354.970 0.000 7354.970
420 8547.663 0.00 8547.66 8522.034 0.000 8522.034
480 9828.785 0.00 9828.79 9802.991 0.000 9802.991
540 11093.931 0.00 11093.93 11067.838 0.000 11067.838
600 12335.993 0.01 12335.99 12309.182 0.000 12309.182

Apply Formula 2 to the 120-port and 600-port samples in the table above to achieve these results:

(32 kbps + 128 kbps) * 120 / 8 = 2400 kb close to 2427 in the table
(32 kbps + 128 kbps) * 600 / 8 = 12000 kb close to 12309 in the table

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This page was last modified on July 11, 2018, at 00:47.