Kevin,
Are there any new dNFS features or enhancements introduced in 12c? I am
particularly interested for storage agnostic features as we use EMC's NAS.
Amir
-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On
Behalf Of Kevin Jernigan
Sent: Wednesday, May 06, 2015 3:02 PM
To: dmarc-noreply@xxxxxxxxxxxxx; oracle-l@xxxxxxxxxxxxx
Subject: Re: Direct NFS and ZS3
Mldaen,
The primary design goal for Direct NFS (dNFS) was / is to provide
SAN-equivalent (or better) performance, in terms of both latency and
throughput, while using NFS / Ethernet infrastructure. A secondary goal is to
simplify the configuration and tuning process for Oracle Database with NFS
storage. dNFS accomplishes these goals by implementing the NFS client inside
Oracle Database, rather then using the OS-supplied "kernel" NFS client. This
allows dNFS to skip some parts of the networking stack, and to skip some of
functionality that is required for a general-purpose NFS client, such as write
ordering. In addition, dNFS creates a separate connection to the NFS server for
each Oracle process, unlike kNFS, which essentially multiplexes all the
processes' I/O's through one or a very small number of connections to the NFS
server.
There are other optimizations in dNFS which provide major performance
improvements over kNFS, and which allow dNFS to auto-configure itself based on
interrogating the NFS server.
In general, if the NFS server can handle the workload, then dNFS can provide
SAN or iSCSI-equivalent performance, with very little configuration work
required of the DBA or system administrator.
More specifically, with Oracle ZFS storage such as ZS3 and ZS4, dNFS includes
additional info with each I/O, which allows the ZS storage to auto-configure to
provide ideal performance for Oracle Database I/O.
This feature is called Oracle Intelligent Storage Protocol - OISP - and is
available starting with Oracle Database 12c.
Bottom line: I know of no good reason to use kNFS instead of dNFS when setting
up Oracle Database with NFS storage, and there are lots of good reasons to
consider dNFS versus iSCSI or FC storage.
-KJ
--
Kevin Jernigan
Senior Director Product Management
Advanced Compression, Hybrid Columnar
Compression (HCC), Database File System
(DBFS), SecureFiles, Database Smart Flash Cache, Total Recall, Database
Resource Manager (DBRM), Direct NFS Client (dNFS), Continuous Query
Notification (CQN), Index Organized Tables (IOT), Information Lifecycle
Management (ILM)
+1-650-607-0392 (o)
+1-415-710-8828 (m)
On 5/6/15 12:49 AM, Mladen Gogala wrote:
On 05/05/2015 12:16 PM, Fernando Jose Andrade wrote:
I don’t know if this configuration is worst than DNFS, I have readThat depends on whether you will utilize iSCSI HBA's like QLogic 4K or
around the web that DNFS beats iSCSI
not. With HBA, I find the iSCSI performance better than NFS. I have no
numbers to share, only an impression. Also, here is a nice little
comparative write-up:
http://www.infoworld.com/article/2616802/infrastructure-storage/your-f
ateful-decision--nfs-or-iscsi-.html
As far as snapshots are considered, ZFS does CoW snapshot, which will
very quickly kill the performance of your appliance. So, since ZS3
already offers file system and is not LUN based, like EMC or NetApp, I
would go with NFS which doesn't require additional pieces of HW (iSCSI
HBA) but would refrain from doing snapshots. As for the choice
between the kernel NFS and dNFS, I usually go with kernel, which is
more standard to configure.
