811517 - GC_INCREMENTAL_DISABLED is being assigned a value of 2

Status: RESOLVED WORKSFORME

(Toolkit :: Telemetry, defect)

Description

[Dave Zeber [:dzeber]]

Attachment: inconsistencies in GC_INCREMENTAL_DISABLED

GC_INCREMENTAL_DISABLED seems to be assigned a value of 2 for some pings. However, for each ping, the fields are all consistent with each other.

I've attached some output from some code to examine the inconsistencies I was seeing. 

Each row corresponds to one session measurement, and column "count" is the number of pings with the measurements listed in the row. The dataset had 44025 pings (from FF v18 Nightly Sep 3-9). Column "n.observations" is the number of values added to the histogram (ie. sum(h$values)) and sum.field is the value of h$sum which accompanied histogram h. Columns n.zeros/ones/twos are the number of observations in each respective bin. 

For booleans and flags we should have sum.field = n.ones + 2*n.twos and n.observations = n.zeros + n.ones + n.twos.

Comment 1

[Dave Zeber [:dzeber]]

Although it seems like it is indeed a boolean: http://mxr.mozilla.org/mozilla-central/source/js/src/gc/Statistics.cpp#541

Comment 2

[Alessio Placitelli [:Dexter]]

Looks like it's working now: https://mzl.la/2AG1dq6 :)