Hi Mark,
Thanks for testing this! Is there any chance I could get you to create
a tracker ticket and upload your data here?
https://tracker.ceph.com/projects/rgw
I doubt very many people have run performance tests on sub-4k byte
objects. In bluestore at least, you'll also get hit by the min-alloc
size which means pretty significant write and space amplification. Out
of curiosity, do you know of many folks or applications that write out
swift/S3 objects this small?
Mark
On 08/28/2018 08:16 AM, Mark Seger wrote:
I tried to include some data and the mail was rejected because of a
suspected virus ;(
Anyhow, running getput to talk to RGW via the swift API with varying
object sizes I discovered GETs of objects with sizes less than 1448
bytes were taking 40msec longer which exactly corresponds to the delay
the nagel alorgithm inserts under certain buffer alignment conditiions.
I found this exact same problem with swift a number of years ago.
The curious thing is I see in
http://docs.ceph.com/docs/master/rados/configuration/network-config-ref/?highlight=public%20addr#tcp
it says nagel IS disabled in rados but maybe not RGW?
-mark
