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Sun Adding Flash Storage to Most of Its Servers
BobB-nw writes "Sun will release a 32GB flash storage drive this year and make flash storage an option for nearly every server the vendor produces, Sun officials are announcing Wednesday. Like EMC, Sun is predicting big things for flash. While flash storage is far more expensive than disk on a per-gigabyte basis, Sun argues that flash is cheaper for high-performance applications that rely on fast I/O Operations Per Second speeds."
People (read: vendors) now frequently refer to flash storage as superior when IOPs are the main issue.
From what I've been able to discern this is actually true only in read-mostly applications and applications where writes are already in neat multiples of the flash erase block size.
If you're doing random small writes your performance is likely to be miserable, because you'll need to erase blocks of flash much larger than the data actually being changed, then rewrite the block with the changed data.
Some apps, like databases, might not care about this if you're able to get their page size to match or exceed that of the underlying storage medium. Whether or not this is possible depends on the database.
For some other uses a log-oriented file system might help, but those have their own issues.
In general, though, flash storage currently only seems to be exciting for random read-mostly applications, which get a revolting performance boost so long as the blocks being written are small enough and scattered enough. For larger contiguous reads hard disks still leave flash in the dust because of their vastly superior raw throughput.
Vendors, however, make a much larger margin on flash disk sales.
This article (PDF) may be of interest:
Understanding Flash SSD performance
(google text version).
It sounds like the SSDs are internal drives for the server. A database would never be stored on an internal hard drive. Almost any commercial database is connected to a disk farm through SAN fabric.
SSDs really shine for OLTP databases. Lots of random IO occurs on these databases (as opposed to data warehouses that use lots of sequential IO).
Normal hard drives are horrible for random IO because of mechanical limitations. Think about trying to switch tracks on a record player thousands of times per second; this is whats happening inside a hard drive (under a random IO load). Its amazing mechanical HDDs work as well as they do.
Re: "Adding a flash storage option" is pretty much an engineering nonevent, and a very minor logistical task.
You have no idea what you are talking about. Sun customers demand that the product Sun sells them have known reliability properties and that Sun guarantees their products properly interact with each other. It takes a significant amount of resources to do this validation. At the same time SSDs and HDDs react very differently to load and can have all sorts of side effects if the OS/application is not prepared to deal with them.