| Subject: Re: S@H servers - are they still down? |
| From: david@djwhome.demon.co.uk (David Woolley |
| Date: 19/05/2004, 07:31 |
In article <5Nuqc.20601$KE6.10018@newsread3.news.atl.earthlink.net>,
sig666 <sig666_lahnospam@yahoo.com> wrote:
Where on the Seti web site does it state the 2 day limit? I have never
seen anything official about a 2 day limit.
Most of the information on this from the Berkeley people has come out
on the newsgroups, particularly sci.astro.seti and particularly from
Eric Korpela. For a long time, and possibly still, the FAQs on the web
site have been misleading. Generally, Berkeley have been poor at
communicating with the people in the field.
There isn't a hard limit for science, but as last documented they need a
couple (might be three) results in effective agreement (rounding errors
can vary slightly, possibly due to different processing platforms and
certainly as a result of when processing interrupted) to meet the science
requirement. They send more than that number of copies in quick succession
in the early life of the work unit.
Most people are processing within less than 12 hours and many people
will be permanently online. That means that by two days very few work
units will not have met the science processing requirements. The 90
percentile is, at a guess, under one day, though. The 50 percentile could
well be under 12 hours.
The optimum number to transmit in the initial burst would be around
(probably slightly less) than the total number of times a work unit is
expected to be processed, as that will free up the space in the work unit
fastest, without causing too much unnecessary processing, on average.
Basically the science limit is set by how long it takes to get a confirmed
result, not by some fixed number of days. From the science point of view,
it is probably better to run without any caching, and go idle if the feed
stalls.