Re: SHMTOTAL

danielyeap@gmail.com wrote: > Hi All, > I came across this line in the Informix 9.3 Administration Guide: > > If messages indicate on a regular basis that the database server needs > more > memory than SHMTOTAL allows, you have not configured the database > server correctly. Lowering the value of BUFFERS or DS_TOTAL_MEMORY is > one possible solution, and increasing the value of SHMTOTAL is another. > > I do not understand why I have to lower the BUFFERS or DS_TOTAL_MEMORY > if I need more memory. I thought I should be increasing those values so > that Informix will have more memory to play with, hence lowering the > risk of needing to dynamically assigning more memory segments to > Informix. > Add this to what Andrew said: You get this message when the engine needs to add an additional virtual shared memory segment (of SHMADD size) to support large/many queries memory requirements beyond what's configured in SHMVIRTSIZE but SHMTOTAL has limited the instance from adding that much more shared memory. So, your options are to 1) raise the limit by increasing SHMTOTAL or 2) to make more of SHMTOTAL available for use by virtual segments by reducing the RESIDENT portion of shared memory which contains BUFFERS, the initial lock table, etc. Unless you have a specific requirement to limit the amount of memory that IDS uses, set SHMTOTAL to zero (0) meaning 'unlimited'. Art S. Kagel