[Gluster-users] Concepts of Gluster: Block- vs File-based | How does cluster internally work?

[Jens Mueller]

Hello Experts,

I would be thankfull for an explanation, what concepts are behind gluster? I
would like to run a database over gluster. As I have read in wikipedia,
running Databases on top of "Block-based Storage Concepts" (like iSCSI)
works quite well. However it seems that Gluster is conceptually nearer to
the NAS Concept with distributing whole files?

However never the less Cluster needs internally also some concepts to
provide random file access...

Some of my Questions:

1.) When requesting a file, is the whole file retrieved or only a portion of
the file?
2.) Are random File accesses supported?
3.) How does cluster internally Workd when the Database (liek MySQL) create
a large file and then accesses this file? Does Cluster shomehow operate on a
"Block Level"? How will an index-scan be translated in reagards how gluster
will access the data on the remote system?

I am very thankfull for any information (also links...) that help me to
understand how gluster internally handles "file accesses" .

(I have reas the "Architecture Document" of Gluster (dont know the exact
name, was hosted on some ftp server of gluster) but this document only
contains marketing language and does not go indepth...)

Thank you very much!!
Jens