We are pushing a metric to cloud watch and would like to create an alarm when the value goes below a certain value.
The problem is that we have maintenance which causes the metric to drop so we don't want to get an alarm during the maintenance window.
I can't see any way of doing this besides disabling the alarm during the maintenance window. Is there a better way of doing this? Can a maintenance window be specified?
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We use Axon 2 to our CQRS-ES
For some (very bad) reasons , we are force to update the content of the eventstore table directly in the database, without using axon. Then we relaunch the axon denormalizer to replay the event and integrate the change in the views
My issue is, when I do it, the newly insert event are not considered by the aggregate ( like there was some sort of cache) .
How can I ask axon to refresh the cache of the eventstore?
I know insert event that way is absolutely not a good practice, but we need a workarround.
There is such a cache. To prevent having to replay all events for that aggregate every time an aggregate instance is loaded, Axon stores a snapshot of the aggregate state every so many events
I think your problem will go away when you delete the snapshots. It's probably in a table called snapshot_event_entry.
https://legacy-docs.axoniq.io/reference-guide/v/2.2/single.html#d5e1274
I need a Java flight recording to diagnose a performance problem on production Weblogic servers. I'd like to also get the Weblogic events. Is there any difference between starting the flight recording from either Java Mission Control (or in my case JCMD) versus initiating a WLDF diagnostic image capture? I understand the WLDF contains zipped files in addition to the .jfr, but right now I'm only interested in the flight recording (.jfr) with both the HotspotJVM and Weblogic events.
The reason I ask is because I notice something in the WLDF docs called Configure WLDF diagnostic volume (off, low, medium, high) where you set what types of Weblogic events you want to record. Will starting a flight recording from JCMD on a weblogic java instance include the Weblogic events at the preconfigured diagnostic volume? Or do you need to start it from the Weblogic Admin Console?
There is no mechanism in WLS that continuously polls to see if a recording has been started, using jcmd or JMC, and if so enable the WLDF events.
You have to enable them separately in the WLDF GUI [1]. When you do that you will also get JVM events roughly corresponding to what you get when you create a default recording. If you want more detailed information (profile), you need to start two seperate recodings.
[1] It can be good to know that the WLDF events are added using bytecode instrumentation, so the events are not even in the code until you enable the diagnostic feature.
Everything recorded into the flight recorder is recorded into the same buffers. See http://hirt.se/blog/?p=370. That said, the WLDF instrumentation settings will throttle what is actually recorded. So, there are various different ways to achieve what you want. The first thing to do is to make sure that you've enabled the diagnostic volume in WLDF to record whatever you want the WLDF to record into the flight recorder. For example "high".
Next you can either:
Start a continuous recording using command line flags, with a template configured to record you are interested in. (For example, the profiling template minus the full thread stack dump events.)
...or use jcmd to start a recording, again referring to the template that specify what, in addition to the WLDF events, you want to record.
...or use JMC to do pretty much the same thing - start a recording with the template settings you are interested in.
The advantage of the first alternative is that the events you are interested in will always be available, even if you dump an arbitrary time period. In the other two alternatives, they will only be available for the time you are running your (presumably) time limited recording. The advantage of the other alternatives is that you only pay for the (usually tiny) additional overhead of the additional events when your recordings are running.
I'm running into an issue I can't fix:
I created a Azure Streaming Analytics Jobs, that sometime run into this error:
Resource usage is over the capacity for one or more of the query steps.
Event processing may be delayed or stop making progress. This may be a
result of large window in your query, large events in your input, large out
of order tolerance window, or a combination of the above. Please try to
partition your query, or break down your query to more steps, and add
Streaming Unit resources from the Scale tab to avoid such condition., :
So I decided to scale up the SU. I stopped the job, I open the scale pane and the input box keep grey. I can't change the SU value, no error message.
What can I do?
Many thanks!
In order to change the SU scale you need admin/owner role on the Azure Stream Analytics job.
Sorry for the inconvenience, we are changing the user experience in order to make this more explicit.
Let me know if it works for you after you get the admin role.
Thanks.,
JS
I currently have CDC enabled on a table for tracking changes done, however while playing around with it. I found out that even though I disable the CDC capture jobs associated with the table, the CT table still tracks all the INSERT and UPDATE done on the table its tracking. I believe that its this capture job that captures changes since this job is always in executing state. So just wondering as to why it still captures even when disabled.
Is this expected? Is there anyway to disable CDC tracking on the table without using sys.sp_cdc_disable_table?
Also, while we are at it would just like to ask how to possibly induce an error to stop this job automatically since I'm trying to recreate an error that made the CDC job stop.
My app gives users the ability to clear a their clipboard after a certain time in seconds after copying some secure text. The problem is, if the app suspends, the clipboard never clears. I've looked at using a background task but I can't find a trigger that suits my needs.
Any advice?
A background task is your best bet, but you have limited options. Ideally you would use a 15 minute timer, but you must be added to the lock screen and I suspect not many users would do that. The 2 hour timer might be your next best option.
A maintenance trigger would be a good option (as that is every 15 minutes and doesn't need to be on the lock screen), but it does require the device to not be on battery power.