VIP23 (VSL refactoring) SLT inventory

Geoff Simmons geoff at
Mon May 6 18:24:47 UTC 2019

To help get an overview of what the VSL refactoring will be all about, I
applied some grep-foo to current master to find the VSL*() calls in the
code, so that we can see how log data are currently formatted by
varnishd. Results are on the github wiki:

This has:

* non-Timestamp VSL*() calls sorted by SLT_* tag, where an SLT_ tag is
identifiable in the code.

* VSLb_ts*() calls (Timestamp logging)

* Some notes about logging struct http (headers & URL & method & reason
& so forth), since that is all encapsulated by functions in
cache_http.c, and hence does appear in a grep for "SLT_".

My grep-foo skillz are average, so I may have missed some things, but
nevertheless this gives us a fair amount of info.

One thing I noticed (that I didn't know before) is that VSL_bin() is
used if and only if the tag is SLT_H2*. That is, the "binary format"
function is used exactly and only for the H2 tags.

** * * UPLEX - Nils Goroll Systemoptimierung

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