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Performance/Metrics
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Revision as of 22:27, 10 January 2019 by imported>Krinkle
This page documents metrics from Performance Team services. Currently in Graphite.
Deployment and monitoring
See Performance/Runbook/Webperf services for the internal details of these services, such as where the metrics originate, and how they are processed/aggregated.
The navtiming-2 metrics are available in Graphite under the frontend.navtiming2
prefix.
Notable differences:
- Offsets are computed relative to fetchStart instead of navigationStart.
- We no longer filter out zero values.
- The sanity filter no longer has an upper bound.
- When the sanity filter encounters negative numbers, it rejects the entire event instead of just the individual data point.
See phab:T104902 for more information about why the metrics were redefined.
Offsets
responseStart
: From PerformanceTiming, relative to fetchStart.firstPaint
: (non-standard)domInteractive
: From PerformanceTiming, relative to fetchStart.domComplete
: From PerformanceTiming, relative to fetchStart.loadEventStart
: From PerformanceTiming, relative to fetchStart.loadEventEnd
: From PerformanceTiming, relative to fetchStart. Also known as "Page load end" or "Total page load time". This typically corresponds with the browser's native page loading indicator.
Deltas
dns
: Computed client-side from PerformanceTimingdomainLookupEnd - domainLookupStart
. (Transmitted as "dnsLookup")unload
: Computed client-side from PerformanceTimingunloadEventEnd - unloadEventStart
.redirect
: Computed client-side from PerformanceTimingredirectEnd - redirectStart
. (Transmitted as "redirecting").mediaWikiLoad
: Computed client-side based on custom mwLoadEnd and mwLoadStart measures. (Transmitted as "mediaWikiLoadComplete").tcp
: Computed server-side asconnectEnd - connectStart
. This includes SSL negotiation.request
: Computed server-side asresponseStart - requestStart
.response
: Computed server-side asresponseEnd - responseStart
.processing
: Computed server-side asdomComplete - responseEnd
.onLoad
: Computed server-side asloadEventEnd - loadEventStart
.ssl
: Computed server-side asconnectEnd - secureConnectionStart
. This is a subset oftcp
.
SaveTiming metrics
SaveTiming get reported to mw.performance.save
in statsd. To see if it's running properly, the mw.performance.save.sample_rate
key should have hits.