X-Mailer: iPhone Mail (5F136)Subject: Capacity planningDate: Thu, 2 Apr 2009 18:09:15 -0400X-Google-Approved: charlie@kx.com via web at 2009-04-02 22:11:24What is the best way in kdb to determine how much memory should we have at runtime for a splay of 350 gb with multiple tablesAny help or guidance or pointers ?
X-Mailer: Apple Mail (2.930.3)usualy you need 4x the size of the largest partition for a table.the above is based on my experience but you should be safe with 8GB RAM.On 3 Apr 2009, at 01:09, Atnmail wrote:>>> What is the best way in kdb to determine how much memory should we> have at runtime for a splay of 350 gb with multiple tables>> Any help or guidance or pointers ?>>> >
X-Mailer: iPhone Mail (5F136)Subject: Re: [personal kdb+] Re: Capacity planningDate: Thu, 2 Apr 2009 18:40:52 -0400Cc: “personal-kdbplus@googlegroups.com” Can u pls give an example of what u mean by largest partition on a table?Also 8 gb seems low as in qa itself we run more than thatOn Apr 2, 2009, at 6:19 PM, Felix Lungu <felix.lungu> wrote:>> usualy you need 4x the size of the largest partition for a table.> the above is based on my experience but you should be safe with 8GB > RAM.>> On 3 Apr 2009, at 01:09, Atnmail wrote:>>>>>>> What is the best way in kdb to determine how much memory should we>> have at runtime for a splay of 350 gb with multiple tables>>>> Any help or guidance or pointers ?>>>>>>>>>> ></felix.lungu>
X-Mailer: Apple Mail (2.930.3)Take the largest daily partition for a table and multiply that by 4.The reason for this is based on the assumption that only few columns are mapped and queried from each partition and the intermediary results can be joined with other columns from other tables.350 GB DB is a small database if you have at least 2 tables of similar size in it. 8GB should be enough unless you want to bring the entire (or large part of it) db in memory. but would be sign of bad design of your queries.But, if are one of the lucky guys which can afford to use local storage of multiple arrays and multiple controllers, you will need to multiply the above figure by the number of logical volumes and run kdb with parallel slaves.FelixOn 3 Apr 2009, at 01:40, Atnmail wrote:>> Can u pls give an example of what u mean by largest partition on a> table?>> Also 8 gb seems low as in qa itself we run more than that>>>> On Apr 2, 2009, at 6:19 PM, Felix Lungu <felix.lungu> wrote:>>>>> usualy you need 4x the size of the largest partition for a table.>> the above is based on my experience but you should be safe with 8GB>> RAM.>>>> On 3 Apr 2009, at 01:09, Atnmail wrote:>>>>>>>>>>> What is the best way in kdb to determine how much memory should we>>> have at runtime for a splay of 350 gb with multiple tables>>>>>> Any help or guidance or pointers ?>>>>>>>>>>>>>>>>>>> ></felix.lungu>