zrepl/daemon
Christian Schwarz 10a14a8c50 [#307] add package trace, integrate it with logging, and adopt it throughout zrepl
package trace:

- introduce the concept of tasks and spans, tracked as linked list within ctx
    - see package-level docs for an overview of the concepts
    - **main feature 1**: unique stack of task and span IDs
        - makes it easy to follow a series of log entries in concurrent code
    - **main feature 2**: ability to produce a chrome://tracing-compatible trace file
        - either via an env variable or a `zrepl pprof` subcommand
        - this is not a CPU profile, we already have go pprof for that
        - but it is very useful to visually inspect where the
          replication / snapshotter / pruner spends its time
          ( fixes #307 )

usage in package daemon/logging:

- goal: every log entry should have a trace field with the ID stack from package trace

- make `logging.GetLogger(ctx, Subsys)` the authoritative `logger.Logger` factory function
    - the context carries a linked list of injected fields which
      `logging.GetLogger` adds to the logger it returns
    - `logging.GetLogger` also uses package `trace` to get the
      task-and-span-stack and injects it into the returned logger's fields
2020-05-19 11:30:02 +02:00
..
filters endpoint: refactor, fix stale holds on initial replication failure, zfs-abstractions subcmd, more efficient ZFS queries 2020-04-18 12:26:03 +02:00
hooks [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
job [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
logging [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
nethelpers format source tree using goimports 2019-03-22 19:41:12 +01:00
pruner [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
snapper [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
control.go zfs: introduce pkg zfs/zfscmd for command logging, status, prometheus metrics 2020-04-05 20:47:25 +02:00
daemon.go [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
main.go [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
pprof.go [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00
prometheus.go [#307] add package trace, integrate it with logging, and adopt it throughout zrepl 2020-05-19 11:30:02 +02:00