Bluestore Compression Configuration and Testing Methodology
To understand the performance aspect of BlueStore compression, we ran several tests as described below: 1. 40 instances running on Red Hat Openstack Platform 10 with one Cinder volume attached per instance(40xRBD volumes).
We then created and mounted a XFS filesystem using the attached Cinder volume. 2. 84xRBD volumes using the FIO libRBD IOengine..
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Bluestore Compression Internals
Bluestore won’t compress any write that is equal or less than the configured min_alloc_size.
In a deployment with default values the min_alloc_size for SSDs is 16KiB and 64 KiB for HDDs.
In our case we are using all-flash(SSDs) media and there would be no compression attempt by Ceph with IOs under 32KiB in size.
To be able to test compression perfo.
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Bluestore Compression on MySQL Database Pool
So far we have discussed about synthetic performance testing based on FIO, automated by PBench-Fio.
To understand the performance implication of BlueStore compression in a close-to-real production workload, we tested multiple MySQL database instances performance on a compressed and uncompressed storage pool.
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Does CEPH object gateway support server-side compression?
This document is for a development version of Ceph.
New in version Kraken.
The Ceph Object Gateway supports server-side compression of uploaded objects, using any of Ceph’s existing compression plugins.
The Reef release added a compress-encrypted zonegroup feature to enable compression with Server-Side Encryption.
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How do I enable/disable compression on a Ceph pool?
Compression can be enabled or disabled on each Ceph pool created on BlueStore OSDs.
In addition to this, using the Ceph CLI the compression algorithm and mode can be changed anytime, regardless of whether the pool contains data or not.
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How does compression work in Ceph?
But first, how does compression work in ceph, or Wise Cluster since we based it on ceph.
There are two (actually three but ms compression is out of scope) places where we can have compression in ceph:
- Object gateway (RGW):
- Server-side compression of uploaded objects
Bluestore:Inline
compression of
data blocks just before writing to disk.
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Large Block (1Mb) : Fio Synthetic Benchmarking
Similar to a small block size, we have also tested large block size workloads with different compression modes.
As such we have tested aggressive, force and no-compression modes.
As shown in chart 4, the aggregated throughput of aggressive and force modes are very comparable, we haven’t observed significant performance differences.
Other than rando.
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MySQL Test Methodology
Bluestore was configured in the same way as in the previous tests, using the snappy algorithm and aggressive compression mode.
We deployed 20 VM instances on OpenStack, which were hosted on 5 compute nodes.
Out of these 20 VM instances, 10 VMs were used as MySQL database instances, while remaining 10 instances were MySQL database clients, as such c.
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MySQL Test Results
The space savings you can achieve with Bluestore compression are entirely dependent on the compressibility of the application workload as well as the compression mode used.
With the Mysql compression tests the combination of the Sysbench generated dataset and the bluestore default compression_required_ratio(0.875) with aggressive compression, we ha.
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Test Lab Configuration
The test lab consists of 5 x RHCS all-flash (NVMe) servers and 7 x client nodes, the detailed hardware, and software configurations are shown in table 1 and 2 respectively.
Please refer to this blog post, for more details about Lab Setup.
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What is red hat Ceph storage 'on-the-fly data compression'?
With the BlueStore OSD backend, Red Hat Ceph Storage gained a new capability known as “on-the-fly data compression” that helps save disk space.
Compression can be enabled or disabled on each Ceph pool created on BlueStore OSDs.
