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From Sattam Alsubaiee <salsuba...@gmail.com>
Subject Re: How to set the lsm component size?
Date Mon, 12 Sep 2016 19:16:00 GMT
The 128M is shared by all the memory components of the primary index and
all its secondary indexes across all io devices on that node.
Also the in-memory components usually usually has fill factor of 75% since
the pages are 75% full and the remaining 25% is un-utilized.

The page size that you have set 128KB looks reasonable for most cases. Your
best bet is to increase the value of storage.memorycomponent.numpage to a
higher number.

Sattam


On Mon, Sep 12, 2016 at 11:33 AM, Jianfeng Jia <jianfeng.jia@gmail.com>
wrote:

> Dear devs,
>
> I’m using the `no-merge` compaction policy and find that the physical
> flushed on-disk component is smaller than I was expected.
>
> Here are my related configurations
>
>   <property>
>     <name>storage.memorycomponent.pagesize</name>
>     <value>128KB</value>
>     <description>The page size in bytes for pages allocated to memory
>       components. (Default = "131072" // 128KB)
>     </description>
>   </property>
>
>   <property>
>     <name>storage.memorycomponent.numpages</name>
>     <value>1024</value>
>     <description>The number of pages to allocate for a memory component.
>       (Default = 256)
>     </description>
>   </property>
>
> With these two settings, I’m expecting the lsm component should be 128M.
> However, the flushed one is about 16M~ 20M. Do we have some compression for
> the on-disk components? If so, it will be good. Otherwise, could someone
> help me to increase the component size? Thanks!
>
> Best,
>
> Jianfeng Jia
> PhD Candidate of Computer Science
> University of California, Irvine
>
>

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