Thanks Rohit. 

Once you play with the page size - set it to say 40, then the issues show up. 
This also affects the number of cluster calculations as well.

-----Original Message-----
From: Rohit Yadav [mailto:rohit.ya...@shapeblue.com] 
Sent: Thursday, May 12, 2016 11:44 AM
To: dev@cloudstack.apache.org
Subject: RE: Metrics UI - Incorrect metrics data for zone/cluster

Rashmi,

Originally, the feature was implemented using all the available list APIs in 
future we may have a backend metrics API instead of aggregation in the 
UI/client side (done right now).
This feature assumes that no single cluster would have 500 hosts (also not 
supported by many hypervisors to have 500+ hosts in a single cluster), the 
calculations are done for each cluster in the cluster metrics view; similarly 
in zones metrics view calculations are done looping through clusters per zone.

Feel free to assign the issue to me, I'll get back to you later.

Regards.

Regards,

Rohit Yadav

rohit.ya...@shapeblue.com
www.shapeblue.com
53 Chandos Place, Covent Garden, London  WC2N 4HSUK @shapeblue

-----Original Message-----
From: Rashmi Dixit [mailto:rashmi_di...@accelerite.com]
Sent: Thursday, May 12, 2016 10:12 AM
To: dev@cloudstack.apache.org
Subject: Metrics UI - Incorrect metrics data for zone/cluster

Hi,

I came across an issue in the metrics for zone and cluster. I have logged a bug 
for the same. https://issues.apache.org/jira/browse/CLOUDSTACK-9377

To quickly summarize the issue: APIs have a pagesize restriction - the 
default.page.size global setting is used as the max result count - value is 
typically 500. In this case, listClusters and listHosts APIS are used to gather 
metrics data for zone and clusters. If there are 600 hosts, then one call to 
listHosts will only return 500 hosts. The usage data is summed up for 500 
hosts, however average is calculated based the total hosts which is 600.

To correct this, UI should fetch ALL hosts for ALL clusters to get the right 
result. Ideally this kind of calculation should be done at the API level - 
large number of hosts will result in performance degradation. The right way to 
fix this would be to add a new API for metrics calculations at zones/cluster 
level.

@Rohit, since you are the original contributor, can you help me with the 
background on this? Any comments/suggestions on doing this differently are most 
welcome.

Thanks!
Rashmi

Rashmi Dixit
Principal Product Engineer | CloudPlatform | www.accelerite.com




DISCLAIMER
==========
This e-mail may contain privileged and confidential information which is the 
property of Accelerite, a Persistent Systems business. It is intended only for 
the use of the individual or entity to which it is addressed. If you are not 
the intended recipient, you are not authorized to read, retain, copy, print, 
distribute or use this message. If you have received this communication in 
error, please notify the sender and delete all copies of this message. 
Accelerite, a Persistent Systems business does not accept any liability for 
virus infected mails.



DISCLAIMER
==========
This e-mail may contain privileged and confidential information which is the 
property of Accelerite, a Persistent Systems business. It is intended only for 
the use of the individual or entity to which it is addressed. If you are not 
the intended recipient, you are not authorized to read, retain, copy, print, 
distribute or use this message. If you have received this communication in 
error, please notify the sender and delete all copies of this message. 
Accelerite, a Persistent Systems business does not accept any liability for 
virus infected mails.

Reply via email to