Hi all. I'm planning on putting a COMSTAR box together shortly for a very specific purpose.
For a long time now, I've had a meta-data latency, contention and performance issue with my SAM-QFS infrastructure. In isolating these problems, we discovered a lot of it came from disk %b and queues for FC connected 10k/15k spindles. A popular method of bringing these metadata latency bottlenecks and points of contention down are SSD and Flash based devices. In looking at a lot of the solutions currently available, they are either: 1. Economically not viable 2. Not flexible enough to put on an FC loop (Texas Memory Systems do offer this, however) 3. Don't provide the output options we want ...so, COMSTAR is being considered. The plan: 1. An x4270 or something to this effect loaded with several Sun F20 FLASH FMOD's 2. zpool "stripe" 2 of the modules, then another 2 and then zpool mirror the stripes 3. Export out of the box over 2 * 8Gbit/sec HBA's 4. Import to SAM-FS meta data controller, over FC 5. Create a zvol atop the presented zpool 6. mksamfs mm devices ontop of the zvol ...watch it fly like no tomorrow :-). So, putting to one side the particulars of SAM-FS and it's tunables, which is an entire conversation in itself, does this seem sane for a high performance, extremely low latency workload, which needs to be "portable" between meta data controllers? (Hence, not putting it directly into a SAS HBA/direct connecting flash storage to the meta data controller, and putting it on an FC loop!). My concerns: 1. I don't know enough about COMSTAR's FC stack/wire speed performance. Can somebody speak to me of this? 2. The future of COMSTAR. Where is it going? What will become of it once Oracle really move in for business? Can I rely on it's existence for a couple of years? 3. Stability. Meta data slices are of a critical nature. SCSI transport errors - just not tolerable. Is COMSTAR really solid and mature enough to live up to high scale, production big data hauling? Thanks all. z -- This message posted from opensolaris.org _______________________________________________ storage-discuss mailing list storage-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/storage-discuss
