As promised, I have conducted an unofficial test of the amount of bandwidth that DIMES uses in an effort to give some guidance to people who run it on Internet connections with download limits.
Previous discussions on this subject have come up with a figure of 1Kb/second. This equates to just over 2.5Gb/month for each instance of DIMES running. Clearly this is a problem for people with small quotas and initial tests made me suspect that this may be total bandwidth and not just download.
I have been running DIMES on 8 devices, pretty much 24/7 along with my other usual Internet activity for half a month now. I was going to let it run for a whole month but I lost one machine yesterday and will be turning them all off for a couple of days in one week time. Therefore, I will publish my results today.
Here is the screenshot from the usage statistics of my ISP Control Panel this morning:
The Off-Peak usage is between midnight and 8am, and the only things that run during this time are DIMES and WCG WU upload/downloads. Therefore, it would be fair to assume that if this represents 8 hours of DIMES traffic then multiplying it by 3 will give us the overall usage.
683.29Mb x 3 = 2049.87Mb = ~2Gb usage in half a month = 4Gb per month
As I mentioned, I am running this on 8 devices. So the figure works out at 512Mb per month per device.
I'm also running this at full speed, which is to take a measurement every 15 seconds. The default setting is to take a measurement every 30 seconds. Given that this doubles the length of time between measurements it is fair to assume that the time between sending and receiving files from the DIMES server will also double so that traffic over the same period of time will halve.
Therefore, my conclusion is that the DIMES Download traffic is:
~256Mb Download per DIMES agent per Month @ 30 Second Measurements (Default)
~512Mb Download per DIMES agent per Month @ 15 Second Measurements (Maximum)
My ISP only grades my quota on download statistics and therefore I have no information for upload. I imagine that this may be larger due to the way DIMES works, so if you get your upload restricted as well then you may need to take this into account.
In conclusion, work out how much download bandwidth you can let DIMES use and configure the measurements gap accordingly (in Agent -> Properties -> Network)
~512Mb per month: 15 Seconds
~256Mb per month: 30 Seconds
~128Mb per month: 60 Seconds
~64Mb per month: 120 Seconds
~32Mb per month: 240 Seconds
The minimum speed that the agent will run at is to take a measurement every 315 seconds, which will use ~24.5Mb based on this calculation.
Please do not take this information as gospel, it is only posted here as an indication from my own installations. If anyone has any thoughts on my calculations, or has any additional information then let me know.
