I think there is no public API available to do this. In this case, the best you can do might be unpersist some RDDs manually. The problem is that this is done by RDD unit, not by block unit. And then, if the storage level including disk level, the data on the disk will be removed too.
Best Regards, Raymond Liu From: 牛兆捷 [mailto:nzjem...@gmail.com] Sent: Thursday, September 04, 2014 2:57 PM To: Liu, Raymond Cc: Patrick Wendell; u...@spark.apache.org; dev@spark.apache.org Subject: Re: memory size for caching RDD Oh I see. I want to implement something like this: sometimes I need to release some memory for other usage even when they are occupied by some RDDs (can be recomputed with the help of lineage when they are needed), does spark provide interfaces to force it to release some memory ? 2014-09-04 14:32 GMT+08:00 Liu, Raymond <raymond....@intel.com>: You don’t need to. It is not static allocated to RDD cache, it is just an up limit. If you don’t use up the memory by RDD cache, it is always available for other usage. except those one also controlled by some memoryFraction conf. e.g. spark.shuffle.memoryFraction which you also set the up limit. Best Regards, Raymond Liu From: 牛兆捷 [mailto:nzjem...@gmail.com] Sent: Thursday, September 04, 2014 2:27 PM To: Patrick Wendell Cc: u...@spark.apache.org; dev@spark.apache.org Subject: Re: memory size for caching RDD But is it possible to make t resizable? When we don't have many RDD to cache, we can give some memory to others. 2014-09-04 13:45 GMT+08:00 Patrick Wendell <pwend...@gmail.com>: Changing this is not supported, it si immutable similar to other spark configuration settings. On Wed, Sep 3, 2014 at 8:13 PM, 牛兆捷 <nzjem...@gmail.com> wrote: > Dear all: > > Spark uses memory to cache RDD and the memory size is specified by > "spark.storage.memoryFraction". > > One the Executor starts, does Spark support adjusting/resizing memory size > of this part dynamically? > > Thanks. > > -- > *Regards,* > *Zhaojie* -- Regards, Zhaojie -- Regards, Zhaojie
