Artifact 24924cb693d1755631ecf99c7c559ea8ee21ef1f

File tools/cvs2fossil/lib/c2f_pbreakscycle.tcl part of check-in [00bf8c198e] - The performance was still not satisfying, even with faster recomputing of successors. Doing it multiple times (Building the graph in each breaker and sort passes) eats time. Caching in memory blows the memory. Chosen solution: Cache this information in the database.

Created a new pass 'CsetDeps' which is run between 'InitCsets' and 'BreakRevCsetCycles' (i.e. changeset creation and first breaker pass). It computes the changeset dependencies from the file-level dependencies once and saves the result in the state, in the new table 'cssuccessor'. Now the breaker and sort passes can get the information quickly, with virtually no effort. The dependencies are recomputed incrementally when a changeset is split by one of the breaker passes, for its fragments and its predecessors.

The loop check is now trivial, and integrated into the successor computation, with the heavy lifting for the detailed analysis and reporting moved down into the type-dependent SQL queries. The relevant new method is 'loops'. Now that the loop check is incremental the pass based checks have been removed from the integrity module, and the option '--loopcheck' has been eliminated. For paranoia the graph setup and modification code got its loop check reinstated as an assert, redusing the changeset report code.

Renumbered the breaker and sort passes. A number of places, like graph setup and traversal, loading of changesets, etc. got feedback indicators to show their progress.

The selection of revision and symbol changesets for the associated breaker passes was a bit on the slow side. We now keep changeset lists sorted by type (during loading or general construction) and access them directly.

by aku on 2007-12-02 20:04:40.

## -*- tcl -*-
# # ## ### ##### ######## ############# #####################
## Copyright (c) 2007 Andreas Kupries.
#
# This software is licensed as described in the file LICENSE, which
# you should have received as part of this distribution.
#
# This software consists of voluntary contributions made by many
# individuals.  For exact contribution history, see the revision
# history and logs, available at http://fossil-scm.hwaci.com/fossil
# # ## ### ##### ######## ############# #####################

## Pass IX. This pass goes over the set of symbol based changesets and
## breaks all dependency cycles they may be in. We need a dependency
## tree. Identical to pass VII, except for the selection of the
## changesets.

# # ## ### ##### ######## ############# #####################
## Requirements

package require Tcl 8.4                                   ; # Required runtime.
package require snit                                      ; # OO system.
package require struct::list                              ; # Higher order list operations.
package require vc::tools::log                            ; # User feedback.
package require vc::fossil::import::cvs::cyclebreaker     ; # Breaking dependency cycles.
package require vc::fossil::import::cvs::repository       ; # Repository management.
package require vc::fossil::import::cvs::state            ; # State storage.
package require vc::fossil::import::cvs::integrity        ; # State integrity checks.
package require vc::fossil::import::cvs::project::rev     ; # Project level changesets

# # ## ### ##### ######## ############# #####################
## Register the pass with the management

vc::fossil::import::cvs::pass define \
    BreakSymCsetCycles \
    {Break Symbol ChangeSet Dependency Cycles} \
    ::vc::fossil::import::cvs::pass::breakscycle

# # ## ### ##### ######## ############# #####################
##

snit::type ::vc::fossil::import::cvs::pass::breakscycle {
    # # ## ### ##### ######## #############
    ## Public API

    typemethod setup {} {
	# Define the names and structure of the persistent state of
	# this pass.

	state reading revision
	state reading changeset
	state reading csitem
	return
    }

    typemethod load {} {
	# Pass manager interface. Executed to load data computed by
	# this pass into memory when this pass is skipped instead of
	# executed.
	return
    }

    typemethod run {} {
	# Pass manager interface. Executed to perform the
	# functionality of the pass.

	cyclebreaker breakcmd {::vc::fossil::import::cvs::cyclebreaker break}

	state transaction {
	    cyclebreaker run break-sym [myproc Changesets]
	}

	repository printcsetstatistics
	integrity changesets
	return
    }

    typemethod discard {} {
	# Pass manager interface. Executed for all passes after the
	# run passes, to remove all data of this pass from the state,
	# as being out of date.
	return
    }

    # # ## ### ##### ######## #############
    ## Internal methods

    proc Changesets {} {
	log write 2 breakscycle {Selecting the symbol changesets}
	return [project::rev sym]
    }

    # # ## ### ##### ######## #############
    ## Configuration

    pragma -hasinstances   no ; # singleton
    pragma -hastypeinfo    no ; # no introspection
    pragma -hastypedestroy no ; # immortal

    # # ## ### ##### ######## #############
}

namespace eval ::vc::fossil::import::cvs::pass {
    namespace export breakscycle
    namespace eval breakscycle {
	namespace import ::vc::fossil::import::cvs::cyclebreaker
	namespace import ::vc::fossil::import::cvs::repository
	namespace import ::vc::fossil::import::cvs::state
	namespace import ::vc::fossil::import::cvs::integrity
	namespace eval project {
	    namespace import ::vc::fossil::import::cvs::project::rev
	}
	namespace import ::vc::tools::log
	log register breakscycle
    }
}

# # ## ### ##### ######## ############# #####################
## Ready

package provide vc::fossil::import::cvs::pass::breakscycle 1.0
return