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I agree we should use 2^30s; the problem with publishing in plain bytes is all those places that have int32_t inside; with 2^31 * 2^30 we can publish up to 2^61 which is 10^(0.3*61) or about 10^18. Bytes. 200 TiB (UK Tier 2 capacity) is 204800 GiB = 219902 GB (voila extra 15000 "GB") - if we stick to GB-GiBs then the roundoff error by rounding to int is within +/- 1 GB which I suppose is OK unless you are looking to fine tune something. -j -----Original Message----- From: Dave Newbold [mailto:[log in to unmask]] Sent: 14 September 2006 09:22 To: Jensen, J (Jens) Cc: [log in to unmask] Subject: Re: storage units Hi, Tell me about it - I spend some time yesterday introducing a field called "which factor of 1000 are we using today" into various planning spreadsheets. Can everyone not just give the numbers in bytes? In practice, we should use 2^30 bytes as the 'base unit' of storage, and scale from that. In the same way we don't use Avagadro's number much when buying vegetables. Ho hum. Dave PS: Nobody tell the PHB's about the horribly mixed factors of ten, eight and two we use every time we talk about network bandwidth - some weeks of discussion could ensue. On 14 Sep 2006, at 08:43, Jens Jensen wrote: > Actually no, we're wrong. > > We are or will be publishing in GBs or KBs - should they be > GiBs and KiBs? > > If we publish an integer value with unit 2^30 bytes, how do the > PHB convert them to (integer) 10^9 bytes (little exercise for the > reader to estimate the errors). > > -j > > On Tue, 12 Sep 2006 14:34:41 +0100, Jensen, J (Jens) > <[log in to unmask]> wrote: > >> Yep, that's also my understanding. You sum it up very well. >> >> --jens >> >> -----Original Message----- >> From: GRIDPP2: Deployment and support of SRM and local storage >> management [mailto:[log in to unmask]]On Behalf Of >> [log in to unmask] >> Sent: 12 September 2006 13:24 >> To: [log in to unmask] >> Subject: Re: FW: storage units >> >> >> As I understand this this does not effect the Glue work on any thing >> other than the presentation of the data in the final web pages. We >> should all carry on as before unless we provide the final output >> for the >> Grid monitoring web pages. >> >> Is this how you all feel about this? >> >> Regards >> >> Owen >> >> >> On Tue, 12 Sep 2006 11:35:37 +0100 >> "Jensen, J (Jens)" <[log in to unmask]> wrote: >> >>> FYI. GDB want us to use "marketing" units :-) in accounting. >>> >>> -j >>> >>> -----Original Message----- >>> From: Coles, J (Jeremy) [mailto:[log in to unmask]] >>> Sent: 12 September 2006 11:02 >>> To: GridPP DTeam >>> Subject: FW: storage units >>> >>> >>> >>> >>> -----Original Message----- >>> From: Kors Bos [mailto:[log in to unmask]] >>> Sent: 11 September 2006 18:25 >>> To: 'GDB' >>> Subject: storage units >>> >>> Dear colleagues, >>> >>> after a discussion in the GDB last Wednesday at BNL we decided to >>> use >>> decimal units for disk space. So a KiloByte is 1000 Bytes en a >>> MegaByte is 1000 KiloBytes etc. The names for Kilo- Mega- Giga- >>> Tera- >>> etc. are then correctly used and we don't have to start using names >>> like GeBi- and TeBi- which refer to units in powers of 2. We now >>> have >>> to make sure that all numbers quoted in the tables with resource >>> pledges are indeed in decimal units. Moreover accounting figures >>> also >>> have to follow this standard. Be aware that some Unix commands >>> return >>> binary values. >>> >>> Kors >> ===================================================================== >> ===