Re: [Exist-open] Max number of files in a collection

[<jmf...@cn...>]

Hi Adam,

Adam Retter wrote:
> Have you done much performance testing with eXist? e.g.
> Hardware/Software combinations and JVM's?

Well, I have tested eXist in quite different platforms since one year=20
and a half, and this is the historical order:

*	Sun Ultra60 (only one 360MHz processor) with 512MB and a 9GB SCSI disk.
*	Powerbook G4 500MHz (first generation) with 512MB and 20GB slow IDE dis=
k.
*	Athlon 1.4GHz with 1GB and 500GB SCSI array (with IDE disks) in RAID-3.
*	Acer Laptop with Intel Centrino 1.5GHz, 512MB and 80GB fast IDE disk.
*	Athlon 64 3200+ with 2GB and 120GB SATA disk.

IBM JVM implementation is veeery fast in their processors (G4, POWER4,=20
G5, POWER5). Sun JVM implementation eats *lots* of memory in Solaris=20
Sparc (twice or three times the used one in Intel platforms). Disk=20
performance and speed is crucial when you are using Sun JVM. I think=20
eXist performance can be improved if the transaction log file is located=20
in a partition in a different disk, because it is being synced each time=20
a transaction starts, or finished due rollback or commit. Also, if you=20
have well defined queries, it is worth disabling default full text=20
indexes over the whole document and creating specific ones (either=20
fulltext or not) for the elements/attributes/text you are querying.

And from JVMs point of view, what I have learnt is:

*	In general, if you can choose between 1.4.2 and 5.0 releases, is=20
better the first one (talking about eXist). Perhaps the last one will=20
improve in the future, but now it tends to eat much more memory and is a=20
bit slower than 1.4.2.

*	jrockit from BEA is not recommended, because version 1.4.2 is not able=20
to handle large files (bigger than 2GB), and although 5.0 is able to, it=20
has some bugs. As I told in a previous mail, it had a segmentation fault=20
at the beginning of my tests (it bursted!).

*	Sun JVM is faster in I/O but IBM one wastes less memory.

> Also are you using Tomcat as a container and if so which version?
>=20

No, I'm not using it so. I'm running it in "server" mode.

	Best Regards,
		Jos=C3=A9 Mar=C3=ADa

--=20
Jos=C3=A9 Mar=C3=ADa Fern=C3=A1ndez Gonz=C3=A1lez		e-mail: jmfernandez@cn=
b.uam.es
Tlfn:	(+34) 91 585 54 50		Fax:	(+34) 91 585 45 06
Grupo de Dise=C3=B1o de Proteinas		Protein Design Group
Centro Nacional de Biotecnolog=C3=ADa	National Center of Biotechnology
C.P.: 28049				Zip Code: 28049
C/. Darwin n=C2=BA 3 (Campus Cantoblanco, U. Aut=C3=B3noma), Madrid (Spai=
n)