jv@mh.nl (Johan Vromans) (02/18/90)
In article <4364@mhres.mh.nl> jv@mh.nl (right, that's me) wrote: > I have about 60,000 articles on-line, and my history files (I > have SystemV "history.d/[0-9]" files) total up to about 4Mb. > I'm considering to use dbm in the news software, hoping this will > speed things up. I rebuilt the dbm history file, which grew to > more than 8 Mb in size. Is this normal? I've got three types of responses. 1. All kinds of people explained me the nature of dbm files (sparse files). Nevertheless, the "more than 8 Mb" were *REAL* Mbytes occupied. 2. I was assured that 2.5 times the size of the history file is quite normal for the dbm files. 3. Suggestions to improve news system performance: - Use 'dbz' instead of 'dbm'. This package, written by Jon Zeeff <zeeff@b-tech.ann-arbor.mi.us>, implements a fast 'dbm' subset especially for the NetNews software. This was advised by a number of people (including Jon Zeeff himself). - Use 'Cnews' instead of 'Bnews'. Better still: use 'Cnews' with 'dbz'. This was also advised by a number of people (not including the authors of Cnews), promising 2 to 20 times more performance. What I did? I added 'dbz' to 'Bnews', and added the 'SPOOLNEWS' option (my machine is running short on memory). Now it feels 50-100% faster. I tried 'Cnews', but ran into problems I could not cope with in the relativily small amount of time I allocated to solve the news performance problems. Building Cnews is rather straighforward, but installing it proved rather complex. I missed the possibility to install a 'shadow' news system aside of Bnews. The documentation states that this is possible, since all news tools obey a series of environment variables. However, I could not get it to work properly. Maybe I try again some other time. Everyone who has sent responses to me: thanks a lot! Johan -- Johan Vromans jv@mh.nl via internet backbones Multihouse Automatisering bv uucp: ..!{uunet,hp4nl}!mh.nl!jv Doesburgweg 7, 2803 PL Gouda, The Netherlands phone/fax: +31 1820 62944/62500 ------------------------ "Arms are made for hugging" -------------------------
henry@utzoo.uucp (Henry Spencer) (02/18/90)
In article <JV.90Feb17152452@mhres.mh.nl> jv@mh.nl (Johan Vromans) writes: > 1. All kinds of people explained me the nature of dbm files (sparse > files). Nevertheless, the "more than 8 Mb" were *REAL* Mbytes > occupied. Unfortunately, much of the sparseness is sufficiently fine-grained that the file system can't exploit it very well, especially if the filesystem's block size is large. -- "The N in NFS stands for Not, | Henry Spencer at U of Toronto Zoology or Need, or perhaps Nightmare"| uunet!attcan!utzoo!henry henry@zoo.toronto.edu