Bandwidth as in MBps ? I've seen (warning message in ECC) as much as 200MBps on a single 2.125Gb port, so the math tells me 60 x 60 x 24 x 200 = 17.2TB on a single day. But on FC layer 1 there's the 8b/10b encoding/decoding, so I'd say this 200MBps (which I actually did see) is about 170MBps in user data.
Having said this, you need sufficient spindels in your storage system to sustain this kind of throughput, so with only 5 spindels you're not getting anywhere near that value. An EMC PSE once told me to calculate 10MBps per spindel, so to get 200MBps you'd need at least 20 spindels.
Why 200 MBps ?? I mean to say we are having a port which can support upto 2Gbps so how did you get 200 MBps?? Is there a way to calculate it?? Is it a spec on every switch where I should look at..Please let me know.
The 8b/10b encoding overhead is already built in to the fibre channel spec, so you can in theory get 200 megabytes per second of payload. Actually if every frame had a full payload and was sent at maximum speed (minimum amount of idles, etc.) you could see about 206MB/s in theory of data payload on a 2Gb/s link.
I've seen 201 once. I tuned ECC to report values over 150MBps to me with a thresshold of 2, so after 2 occurences I got an email that some port was doing 201MBps. Cool, hey ?
Can you please mark the post as answered and hand out points for those who helped you ? Next to each post you'll see buttons "helpful" and "correct". "Helpful" means 6 points and you can hand those out twice. The "Correct" means 10 points and you can only hand them out once.
RRR
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I've seen (warning message in ECC) as much as 200MBps on a single 2.125Gb port, so the math tells me 60 x 60 x 24 x 200 = 17.2TB on a single day.
But on FC layer 1 there's the 8b/10b encoding/decoding, so I'd say this 200MBps (which I actually did see) is about 170MBps in user data.
Having said this, you need sufficient spindels in your storage system to sustain this kind of throughput, so with only 5 spindels you're not getting anywhere near that value. An EMC PSE once told me to calculate 10MBps per spindel, so to get 200MBps you'd need at least 20 spindels.
Source: http://en.wikipedia.org/wiki/Fibre_Channel_8B/10B_encoding
Summi1
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sfuhrman
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RRR
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As mentioned Fibre Channel "encapsulates" bytes with 2 extra bits, so each byte is 10 bits.
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Summi1
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July 2nd, 2008 09:00
RRR
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Next to each post you'll see buttons "helpful" and "correct". "Helpful" means 6 points and you can hand those out twice. The "Correct" means 10 points and you can only hand them out once.
RRR
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August 19th, 2008 01:00