You can translate the question and the replies:

Denodo 7.0 - Estimate and Actual Memory Used by a Query

We're encountering an error suggesting a query is too large. How do you derive the estimated and actual memory of a query? -John
user
23-02-2021 13:01:39 -0500

3 Answers

Hi, Going through the question, I believe that the error has occurred, when the executing query consumes more memory than the configured memory limit. Generally, estimating memory usage for a particular query depends on the operations being performed, number of rows retrieved, etc. In scenarios like this, to avoid such errors , I would set a memory limit which can be used by the query. For this, I would open the Memory usage tab by navigating to Administration > Server Configuration of Virtual DataPort Administration Tool for increasing the value of “**Maximum query size (MB)**” parameter and execute the view again. You can refer to the [Configuring the Memory Usage and Swapping Policy](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/server_administration_-_configuring_the_server/configuring_the_memory_usage_and_swapping_policy/configuring_the_memory_usage_and_swapping_policy#configuring-the-memory-usage-and-swapping-policy) section and[ Limit the Maximum Amount of Memory of a Query](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/memory_management/limit_the_maximum_amount_of_memory_of_a_query/limit_the_maximum_amount_of_memory_of_a_query) section under the Virtual DataPort Administration Guide for more information on configuring the memory usage. Hope this helps !
Denodo Team
24-02-2021 07:35:39 -0500
Denodo Team, Thank you for the quick reply. I reviewed the documentation mentioned and have a follow up question. If i set the available memory using the Server Configuration > Memory Usage option, do i inadvertantly create a memory issue for the server by allowing all queries to use more memory? I guess, my original question was really on having enough information related to the actual query to make an informed decision on what the new maximum query limit should be. Do you know if there is additiona logging i can enable which will provide the actual memory used by a query?
user
24-02-2021 09:47:50 -0500
Hi, Generally, the memory limit determines the memory required for executing the query (computing the memory required by swapping or queues at each view level). If the result obtained is higher than the memory limit specified, then Denodo tries to reduce the size of intermediate result sets (until 1MB). Further, at the moment the estimation of actual memory used by a query is not possible. You can refer to [Configuring the Memory Usage and Swapping Policy](https://community.denodo.com/docs/html/browse/7.0/vdp/administration/server_administration_-_configuring_the_server/configuring_the_memory_usage_and_swapping_policy/configuring_the_memory_usage_and_swapping_policy#configuring-the-memory-usage-and-swapping-policy) section under the Virtual DataPort Administration Guide for more information. Hope this helps !
Denodo Team
03-03-2021 07:28:58 -0500
You must sign in to add an answer. If you do not have an account, you can register here