Re: [Quickfix-developers] FileLog, FileStore flush

[Caleb E. <cal...@gm...>]

On 10/7/05, Alexey Zubko <ale...@gm...> wrote:
>
> I want to try to eliminate these flush calls from the classes.
> Is it potential danger? Does anyone have such experience?
> Is it better or faster to use a SQL server to store logs?


It is definitely a potential danger. Any data that hasn't been flushed to
disk (notably the .seqnums and also perhaps the .outgoing file) won't be
written to disk if your process dies unexpectedly or the machine reboots.
When you recover, your application may end up re-processing messages it has
already received. OIr perhaps even worse, unable to resend messages that th=
e
counterparty has not received.

This is a classic safety vs. speed tradeoff. The right answer depends on th=
e
requirements of your own system, and the default implementation of these
classes in QuickFIX takes the safest possible (but also slowest) approach t=
o
guarantee recoverability.

--
Caleb Epstein
caleb dot epstein at gmail dot com