Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!elroy.jpl.nasa.gov!sdd.hp.com!spool.mu.edu!uwm.edu!linac!att!ucbvax!tut.cis.ohio-state.edu!tortoise.cis.ohio-state.edu!meekins From: meekins@tortoise.cis.ohio-state.edu (timothy lee meekins) Newsgroups: comp.sys.apple2 Subject: Re: RamFast Write-Through Cache? Message-ID: <109170@tut.cis.ohio-state.edu> Date: 18 Apr 91 01:38:48 GMT References: <613@generic.UUCP> <1991Apr17.143801.22825@m.cs.uiuc.edu> Sender: news@tut.cis.ohio-state.edu Organization: The Ohio State University, Department of Computer and Information Science Lines: 32 In article joseph@rutgers.rutgers.edu (Seymour Joseph) writes: >In article <1991Apr17.143801.22825@m.cs.uiuc.edu> bazyar@ernie (Jawaid Bazyar) >writes: >> The RAMfast cache is what is termed as "write-through", i.e. any data >>written to the card is immediately written through to the disk. > > >Jawaid, > >I own a RAMfast SCSI card, and your statement conflicts directly with my >experience, and my discussions with CV Technologies. When I write data to >disk, there is often a delay between when the program starts writing data, and >hard disk activity. The cache on the Ramfast is not a write-through cache. >The card is Very fast so the delay is never more than a second or two, but it >is there. > >Seymour Yup, you goofed Jawaid. The RamFast has a "write-deferred" cache. When you write a block of data is stored in a cache and execution is immediately returned to the application. While the GS is off doing something else, the RamFast will begin writing the cache to disk in the background. In other words, it defers the writing until later. This allows for very fast write operations. -- +---------------------------S-U-P-P-O-R-T-----------------------------------+ |/ Tim Meekins <<>> Snail Mail: <<>> Apple II \| |> meekins@cis.ohio-state.edu <<>> 8372 Morris Rd. <<>> Forever! <| |\ timm@pro-tcc.cts.com <<>> Hilliard, OH 43026 <<>> /|