On 02/27/2012 08:59 AM, Reuven M. Lerner wrote:
From what I understand, the issue isn't one of current disk space, but rather of how quickly the disk space is being used up.
Noted. Just keep in mind that dead rows are not free. In the case of sequence scans, the rows still have to be read from disk and then ignored by the engine. Vacuums also act as sequence scans, so the more data they're reading, the longer that takes. This is especially true on an overloaded system.
I wouldn't be surprised if we end up doing a CLUSTER at some point. The problem is basically that this machine is in 24/7 operation at high-speed manufacturing plants, and the best-case scenario is for a 4-hour maintenance window.
The best case scenario is for them to buy a second server. If operation of this app stack really is critical to business, they need to spend the money to keep it working, or they'll end up paying much more for it when it fails. You also said that server has other stuff running on it, and it already has very little memory. That tells me they have no DR node. I'm afraid to even ask how they're doing backups. That one machine is a giant, red, flashing single point of failure. I really hope they understand that.
I've suggested that we might be able to help the situation somewhat by attaching a portable USB-based hard disk, and adding a new tablespace that'll let us keep running while we divide up the work that the disk is doing, but they've made it clear that the current hardware configuration cannot and will not change. Period.
And that's it, then. You have yourself a bad client. If it were me, I'd get through this contract and never do business with them again. They have a system that's basically 100% guaranteed to fail some time in the future (and yet is critical for operation!) and are putting Band-Aids on it. I think there's a parable somewhere about eggs and baskets, but I can't recall it at this moment. ;)
-- Shaun Thomas OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604 312-444-8534 sthomas@xxxxxxxxx ______________________________________________ See http://www.peak6.com/email_disclaimer/ for terms and conditions related to this email -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
