db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Daniel John Debrunner <...@debrunners.com>
Subject Re: [VOTE] Re: Help detecting client disconnects for network server
Date Tue, 12 Oct 2004 01:24:49 GMT
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Jan Hlavatý wrote:

> Kathey Marsden wrote:
>
>>2) Add a property derby.drda.keepAlive={true|false} (defaults to true as
>>described above).  There seems to be a need to be able to turn keepAlive
>>off in some cases.
>
>
> And why is that? Who is worried by keepalive and why?
> There is no overhead associated with it.

Is that true, no overhead, or is it *low* overhead?

- From a quick google search I found this, which indicates keepalive is a
controversial feature.

http://home.student.uu.se/j/jolo4453/projekt/tcpip1/tcp_keep.htm#23_0

(which seems to be this actual book)
http://www.aw-bc.com/catalog/academic/product/0,1144,0201633469-TOC,00.html

See this quote
[quote]
Keepalives are not part of the TCP specification. The Host Requirements
RFC provides three reasons not to use them: (1) they can cause perfectly
good connections to be dropped during transient failures, (2) they
consume unnecessary bandwidth, and (3) they cost money on an internet
that charges by the packet.
[end-quote]

So what would be the downside of allow keep alive to be disabled?

Dan.




-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.5 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD4DBQFBazJhIv0S4qsbfuQRAo8AAJ99J6M7uMb8+nDPbWmQw4xX/6MuswCYxxg1
S4uvbpVeb7Pg83XKmHBY+w==
=2d/M
-----END PGP SIGNATURE-----


Mime
View raw message