Hi Wendy, thanks for the prompt response. I see what you're saying. Just a few things to clarify. The databases I have are clustered active-passive, so only one machine accesses the store at any given time with a persistent connection to the SAN. Also, yes, I would think that for this particular application the IO pattern might be very close to parallel in nature as essentially all cluster nodes will run the same application accessing the same store but may rarely access the same folder at the same time and if they do, it would be independantly of each other. I guess the community involved with the development of this application isn't too familiar with clustered filesystems and they may be considering database storage over shared filesystems such as NFS or something but they seem to suggest that database storage offers better scalability and less administrative overhead. I do care about the administrative overhead but performance is a bigger criteria. The other thing I should point out is that whereas the clustered databases use HBAs to access the SAN the linux cluster nodes running the application will access the SAN using GigE NICs. The performance and CPU overhead of not being able to use HBAs might be an added factor, do you think? I'm totally neutral about either solution, I just want the best performance with whatever I go with, so I wonder if a database person on the list can give their view as well? Best Regards, \R -- Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
