[[sub:cache_metadata]]
=== Separate metadata cache

Gradle keeps a record of various aspects of dependency resolution in binary format in the metadata cache.
The information stored in the metadata cache includes:

* The result of resolving a dynamic version (e.g. `1.+`) to a concrete version (e.g. `1.2`).

	// 1 if not.
	_, err := Run(ctx, r.dir, "git", "merge-base", "--is-ancestor", "--", tag, rev)

	// Git reports "is an ancestor" with exit code 0 and "not an ancestor" with
	// exit code 1.
	// Unfortunately, if we've already fetched rev with a shallow history, git
	// merge-base has been observed to report a false-negative, so don't stop yet
	// even if the exit code is 1!
	if err == nil {
		return true, nil
	}

.. TENCENT
.. everything else
. higher major versions take precedence over lower ones
. higher minor versions take precedence over lower ones
. installation paths take precedence according to their lexicographic ordering (last resort criteria for deterministically deciding
between installations of the same type, from the same vendor and with the same version)

All these rules are applied as multilevel sorting criteria, *in the order shown*.

		_WAIT_TIMEOUT   = 0x00000102
		_WAIT_FAILED    = 0xFFFFFFFF
	)

	var result uintptr
	if ns < 0 {
		result = stdcall2(_WaitForSingleObject, getg().m.waitsema, uintptr(_INFINITE))
	} else {
		start := nanotime()
		elapsed := int64(0)
		for {
			ms := int64(timediv(ns-elapsed, 1000000, nil))
			if ms == 0 {
				ms = 1
			}
			result = stdcall4(_WaitForMultipleObjects, 2,

func (s *socketsFirst) sortAvailableNUMANodes() []int {
	var result []int
	for _, socket := range s.sortAvailableSockets() {
		numas := s.acc.details.NUMANodesInSockets(socket).UnsortedList()
		s.acc.sort(numas, s.acc.details.CPUsInNUMANodes)
		result = append(result, numas...)
	}
	return result
}

// If sockets are higher in the memory hierarchy than NUMA nodes, then just
// sort the sockets directly, and return them.

** It is preferable to use <<composite_builds.adoc#composite_builds, composite builds>> for this use case
** If for some reason neither composite builds nor full featured repository are possible, then `mavenLocal()` is a last resort option

After all these warnings, if you end up using `mavenLocal()`, consider combining it with <<#sec:repository-content-filtering,a repository filter>>.
This will make sure it only provides what is expected and nothing else.

You might also find that you can <<migmvn:unnecessary_plugins,replace a plugin with built-in Gradle functionality>>.
As a last resort, you may need to reimplement a Maven plugin <<migmvn:custom_plugins,via your own custom plugins and task types>>.
+
The rest of this chapter looks in more detail at specific aspects of migrating a build from Maven to Gradle.

[[migmvn:build_lifecycle]]
== Understanding the build lifecycle

	// ev.Args[2] earlier, because it would produce seemingly broken timestamps
	// (misplaced event). We also can't simply update the timestamp and resort
	// events, because if timestamps are broken we will misplace the event and
	// later report logically broken trace (instead of reporting broken
	// timestamps).
	lastSysBlock := make(map[uint64]Timestamp)
	for i := 0; i < events.Len(); i++ {
		ev := events.Ptr(i)

		return total / div
	}
	return total
}

// Report contains the data and associated routines to extract a
// report from a profile.
type Report struct {
	prof        *profile.Profile
	total       int64
	options     *Options
	formatValue func(int64) string
}

// Total returns the total number of samples in a report.
func (rpt *Report) Total() int64 { return rpt.total }

problems-report.png...