Suppose that you currently need 16 GB to cache everything now. I would install (perhaps) 32 GB ram for the initial configuration. The price of memory drops exponentially, and so waiting for the price to drop will give a much lower expense for the cost of the RAM. The reason to double the ram is the expense of upgrading in terms of labor and downtime for the computer. That can be very significant. So if we double the ram, that should give one or (hopefully) two years safety margin. If the database is expected to grow exponentially fast, then that is another issue. In such a case, if it can be cost justified, put on the largest memory volume that is possible given your financial limitations. In any case, plan to completely replace everything (CPU, memory, disk) every 5 years or less. All the value is really in the data. Because hardware increases compute power exponentially over time, that also means that the value of the hardware you bought decreases exponentially over time. -----Original Message----- From: pgsql-general-owner@xxxxxxxxxxxxxx [mailto:pgsql-general-owner@xxxxxxxxxxxxxx] On Behalf Of William Yu Sent: Friday, January 28, 2005 11:36 AM To: pgsql-general@xxxxxxxxxxxxxx Subject: Re: Splitting queries across servers Without memory, the prices are roughly: 4x846 = $5500 4x848 = $6500 4x850 = $8000 Memory costs would be: 16GB (1GB DIMMs) = $3000 32GB (2GB DIMMs) = $7500 64GB (4GB DIMMs) = $24000 128GB (8GB DIMMs) = $60000 The prices on the 4GB & 8GB DIMMs are bleeding edge of course. I see a wide range of for them on Froogle. You will want your vendor of course to pick memory is proper for the MB and pay whatever premium they'll charge ontop of it. (Looking at the Tyan website, they only list 2GB DIMMs as supported for their Quad Opteron MBs but whether that's because those specs were done before >= 4GB DIMMs were available or an actual hardware limitation, I dunno.) Max wrote: >> >>With a Quad Opteron (4 memory slots per CPU), you could put 64GB of RAM >>onto a single machine using 4GB DIMMs in every slot. > > > We were talking about a similar solution today, but not quite as good as > this. You really got me thinking now. 64Gb.. hm that would solve many > issues. what do you think the cost would be for such a beast ? Any idea ? > > Max > > > > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend > ---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to majordomo@xxxxxxxxxxxxxx) ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
