[ https://issues.apache.org/jira/browse/SPARK-23206?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Edwina Lu updated SPARK-23206: ------------------------------ Attachment: (was: StageTab.png) > Additional Memory Tuning Metrics > -------------------------------- > > Key: SPARK-23206 > URL: https://issues.apache.org/jira/browse/SPARK-23206 > Project: Spark > Issue Type: Improvement > Components: Spark Core > Affects Versions: 2.2.1 > Reporter: Edwina Lu > Priority: Major > Attachments: ExecutorsTab.png, MemoryTuningMetricsDesignDoc.pdf > > > At LinkedIn, we have multiple clusters, running thousands of Spark > applications, and these numbers are growing rapidly. We need to ensure that > these Spark applications are well tuned – cluster resources, including > memory, should be used efficiently so that the cluster can support running > more applications concurrently, and applications should run quickly and > reliably. > Currently there is limited visibility into how much memory executors are > using, and users are guessing numbers for executor and driver memory sizing. > These estimates are often much larger than needed, leading to memory wastage. > Examining the metrics for one cluster for a month, the average percentage of > used executor memory (max JVM used memory across executors / > spark.executor.memory) is 35%, leading to an average of 591GB unused memory > per application (number of executors * (spark.executor.memory - max JVM used > memory)). Spark has multiple memory regions (user memory, execution memory, > storage memory, and overhead memory), and to understand how memory is being > used and fine-tune allocation between regions, it would be useful to have > information about how much memory is being used for the different regions. > To improve visibility into memory usage for the driver and executors and > different memory regions, the following additional memory metrics can be be > tracked for each executor and driver: > * JVM used memory: the JVM heap size for the executor/driver. > * Execution memory: memory used for computation in shuffles, joins, sorts > and aggregations. > * Storage memory: memory used caching and propagating internal data across > the cluster. > * Unified memory: sum of execution and storage memory. > The peak values for each memory metric can be tracked for each executor, and > also per stage. This information can be shown in the Spark UI and the REST > APIs. Information for peak JVM used memory can help with determining > appropriate values for spark.executor.memory and spark.driver.memory, and > information about the unified memory region can help with determining > appropriate values for spark.memory.fraction and > spark.memory.storageFraction. Stage memory information can help identify > which stages are most memory intensive, and users can look into the relevant > code to determine if it can be optimized. > The memory metrics can be gathered by adding the current JVM used memory, > execution memory and storage memory to the heartbeat. SparkListeners are > modified to collect the new metrics for the executors, stages and Spark > history log. Only interesting values (peak values per stage per executor) are > recorded in the Spark history log, to minimize the amount of additional > logging. > We have attached our design documentation with this ticket and would like to > receive feedback from the community for this proposal. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org