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From Sattam Alsubaiee <salsuba...@gmail.com>
Subject Re: How to set the lsm component size?
Date Mon, 12 Sep 2016 19:50:15 GMT
This is the total memory size given for all datasets. Think of it as the
buffer cache for all memory components of all indexes in that machine. When
it is exhausted, a victim dataset must be evicted and closed to have a
space for another dataset.

On Mon, Sep 12, 2016 at 12:29 PM, Jianfeng Jia <jianfeng.jia@gmail.com>
wrote:

> I was a little confused, there is another configuration:
>
> storage.memorycomponent.globalbudget ( which I set to 4G)
>
> I was thinking this is the budget that every component on one partition is
> shared. Is that the case?
>
> > On Sep 12, 2016, at 12:16 PM, Sattam Alsubaiee <salsubaiee@gmail.com>
> wrote:
> >
> > 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
> >>
> >>
>
>
>
> Best,
>
> Jianfeng Jia
> PhD Candidate of Computer Science
> University of California, Irvine
>
>

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