[Info-vax] Databases versus RMS

[glen herrmannsfeldt]

Johnny Billquist <bqt at softjar.se> wrote:

(snip, someone wrote)
>> You are mixing read and write cache. Make sure you are talking
>> about the same thing before arguing... :-)

> Huh? They are not separate! If they were, you'd get some really bad results.

> But even disregarding that, I do not understand what you were 
> commenting. Please explain.

More specifically, the difference between write-through and write-back.
A write-back cache always writes to the underlying (RAM or disk)
storage system, though the data is also available for later read.

It was an NFS tradition for write operations not to return (acknowledge)
until the data was on the physical disk. It would do read-ahead caching
to speed up read operations, though.

-- glen