view contrib/memory.py @ 51423:7c6d0b9dde37

rust-index: improve phase computation speed

While less memory efficient, using an array is *much* faster than using a
HashMap, especially with the default hasher. It even makes the code simpler,
so I'm not really sure what I was thinking in the first place, maybe it's more
obvious now.

This fix a significant performance regression when using the rust version of the
code. (however, the C code still outperform rust on this operation)

hg perf::phases on mozilla-try-2023-03-22
- 6.6.3:  0.451239 seconds
- before: 0.982495 seconds
- after:  0.265347 seconds
- C code: 0.183241 second

# memory.py - track memory usage
#
# Copyright 2009 Olivia Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''helper extension to measure memory usage

Reads current and peak memory usage from ``/proc/self/status`` and
prints it to ``stderr`` on exit.
'''


def memusage(ui):
    """Report memory usage of the current process."""
    result = {'peak': 0, 'rss': 0}
    with open('/proc/self/status', 'r') as status:
        # This will only work on systems with a /proc file system
        # (like Linux).
        for line in status:
            parts = line.split()
            key = parts[0][2:-1].lower()
            if key in result:
                result[key] = int(parts[1])
    ui.write_err(
        ", ".join(
            ["%s: %.1f MiB" % (k, v / 1024.0) for k, v in result.iteritems()]
        )
        + "\n"
    )


def extsetup(ui):
    ui.atexit(memusage, ui)