Node diversity work

classic Classic list List threaded Threaded
1 message Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Node diversity work

SEN, Ramen (NHS DIGITAL)

As part of a series of improvements and ongoing work on Riak KV we are doing here at NHS Digital, I have added a new bucket option to Riak KV, called 'node_confirms'.


In summary, within the database clusters used for the NHS Spine, historically we have used the primary write option (pw=2) to ensure data isn't lost due to individual hardware failures, as a proxy for physical diversity guarantees. This has worked well, however can lead to a situation where a riak database cluster rejects some writes in the case of two node failures.

The solution is to more directly tie configuration options over diversity to the physical layout of the system at run-time, not the abstract concept of the ring, and the new node_confirms option allows operators to specify the number of diverse nodes that must confirm their writes before a write is considered successful.

Next Friday Martin (@masleeds) is planning to do a write-up of the testing so far of the core node_worker_pool to help with multi-data-centre anti-entropy.

Regards,
Ramen


Dr Ramen Sen
Lead Systems Engineer
Operations and Non-functional Test Lead
Spine 2 Core
NHS Digital

[hidden email]

NHS Digital provides information and technology for better health and care.
Find out more about who we are and what we do at  www.digital.nhs.uk

@NHSDigital
[hidden email]
General enquiries: 0300 303 5678



********************************************************************************************************************

This message may contain confidential information. If you are not the intended recipient please inform the
sender that you have received the message in error before deleting it.
Please do not disclose, copy or distribute information in this e-mail or take any action in relation to its contents. To do so is strictly prohibited and may be unlawful. Thank you for your co-operation.

NHSmail is the secure email and directory service available for all NHS staff in England and Scotland. NHSmail is approved for exchanging patient data and other sensitive information with NHSmail and other accredited email services.

For more information and to find out how you can switch, https://portal.nhs.net/help/joiningnhsmail


_______________________________________________
riak-users mailing list
[hidden email]
http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
Loading...