thanks "KwikOne" very nicely explained!! On Thu, Mar 4, 2010 at 5:50 PM, KwikOne <[email protected]> wrote:
> Coalwater, > The 'granularity' is the 'slice' of time used for the calculations > (this could be > either actual time slots or 'elapsed time'). The smaller the > granularity the > larger the variations will appear in a graph. Using the previous > example if > the calculation was done with a once a second granularity (I will > presume > that a 1400 Byte chunk arrives each 100 ms.) which would mean that > there > would have been 1400 + 1400 * 10 chunks = 15,400 Bytes in the first > second = 15,400 Bytes per second as the first point; but the second > point > would only have 1400 * 10 = 14,000 Bytes/second, a much lower > difference. > > On Feb 28, 6:53 pm, Mohammad AbuShady <[email protected]> wrote: > > I see, thanks a lot, and for your question about where the speed is being > > show, it's both in the download window (firefox download window) and also > a > > network speed monitor over the whole system, of course they don't show > the > > same numbers but they both show the small increase in the start, and I > don't > > really know what 'granularity' means. > > > > ~Coalwater~ > > > > On Mon, Mar 1, 2010 at 1:33 AM, KwikOne <[email protected]> wrote: > > > You did not indicate "where" your download speed is being shown/ > > > calculated, nor the time > > > granularity used. Quite often the speed spike are not really spikes > > > (especially when first > > > starting the download) because of the way the download speed is being > > > calculated and > > > as time goes on the download speed stays constant, or it will drop off > > > then stay constant. > > > Think of it this way (note the figures are just approximates as > > > illustration only with rounding)... > > > 1) download requested from server > > > 2) first bit of data arrives; calculated speed is roughly amount of > > > data / 1 ms. (smallest granularity) > > > = very high speed (1000 times amount of data) > > > (example - first chunk is 1400 Byte, this would give approx > > > 1,400,000 Byte/sec rate) > > > 3) next bit of data arrives; calculated speed is roughly total amount > > > of data / (time from first bit > > > to second bit) = lower speed (unless the server is close enough > > > that you have < 1ms time) > > > (example - second chunk 1400 Byte arrives 100 ms later which would > > > give approx > > > 2800 Byte for 100 ms. = 28,000 Byte/sec). > > > 4) next bit of data arrives (example 1400 Byte 100 ms later which > > > calculates out to > > > 4200 Byte in 200 ms. = 21,000 Byte/sec). > > > and so on... get the picture (it all depends upon how the calculations > > > are done)? > > > Notice how the rate is dropping off when in actual fact in this > > > example it is actually 14,000 Byte/sec. > > > > > On Feb 22, 7:37 pm, Coalwater <[email protected]> wrote: > > > > Well i noticed that i when ever i start a download, the download > speed > > > > starts with a very high speed spike in the beginning that could reach > > > > up to 3x of my bandwidth, and last for like 3 to 10 secs then starts > > > > to gradually drop till it reaches my usual expected download speed, > > > > this isn't really a problem but i would really like to understand it > > > > from the networks point of view, how does it get past the ISP limit > > > > even if for a very short period of time, because i might think of > > > > using it to my advantage somehow if i understand it, Hope some > > > > networks guy around here could explain to me :D > > > > oh and it doesn't depend on the connection type nor the operating > > > > system, i saw this happen on cable connection and mobile broadband, > > > > windows and ubuntu so it doesn't have any thing to do with those > > > > differences.. oh and it works also with both normal single connection > > > > download and download accelerators that use multipart downloading > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Computer Tech Support" group. > > > To post to this group, send email to > > > [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]<computer-tech-support%[email protected]> > <computer-tech-support%[email protected]<computer-tech-support%[email protected]> > > > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/computer-tech-support?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "Computer Tech Support" group. > To post to this group, send email to > [email protected]. > To unsubscribe from this group, send email to > [email protected]<computer-tech-support%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/computer-tech-support?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Computer Tech Support" group. 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