svn commit: r302288 - head/release/tools

[Colin Percival]

On 06/29/16 17:01, Bryan Drewery wrote:
> On 6/29/2016 4:56 PM, Colin Percival wrote:
>> Author: cperciva
>> Date: Wed Jun 29 23:56:24 2016
>> New Revision: 302288
>> URL: https://svnweb.freebsd.org/changeset/base/302288
>>
>> Log:
>>   Enable indirect segment I/Os by default in the Xen blkfront driver when
>>   running on EC2.  Due to improvements in EC2, the performance penalty which
>>   was present on some EC2 instances no longer exists, and enabling this
>>   feature now consistently yields ~20% higher throughput with equal or lower
>>   latency.
> 
> Does this rely on any driver updates / is it safe to make the same
> change on my existing 10.2 system?

The relevant driver code is only in 10.3 and later.  I'm not absolutely
certain if already-running EC2 instances have the EC2 performance fix,
either; you might need to launch a new instance in order to be guaranteed
of the performance benefits.

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid