nprescott · HackerTrans

3 jaar geledendiscuss

This reminded me of a prior discussion[0] on bulk data generation in SQLite with Rust (vs Python vs PyPy) which previously led me to trying out two different techniques using just SQLite[1]. The approach here is so similar I tried my prior solution on the slowest VPS I have access to (1 vCPU core 2.4GHz, 512Mi, $2.50/month from vultr):

    sqlite> create table users (id blob primary key not null, created_at text not null, username text not null);
    sqlite> create unique index idx_users_on_id on users(id);
    sqlite> pragma journal_mode=wal;
    sqlite> .load '/tmp/uuid.c.so'
    sqlite> .timer on
    sqlite> insert into users(id, created_at, username)
            select uuid(), strftime('%Y-%m-%dT%H:%M:%fZ'), 'hello'
            from generate_series limit 100000;
    Run Time: real 1.159 user 0.572631 sys 0.442133

where the UUID extension comes from the SQLite authors[2] and generate_series is compiled into the SQLite CLI. It is possible further pragma-tweaking might eke out further performance but I feel like this representative of the no-optimization scenario I typically find myself in.

In the interest of finding where the bulk of the time is spent and on a hunch I tried swapping the UUID for plain auto-incrementing primary keys as well:

    sqlite> insert into users(created_at, username) select strftime('%Y-%m-%dT%H:%M:%fZ'), 'hello' from generate_series limit 100000;
    Run Time: real 0.142 user 0.068090 sys 0.025507

Clearly UUIDs are not free!

[0]: https://news.ycombinator.com/item?id=27872575

[1]: https://idle.nprescott.com/2021/bulk-data-generation-in-sqli...

[2]: https://sqlite.org/src/file/ext/misc/uuid.c

nprescott

4 jaar geledendiscuss

PEP-508[0] explains the grammar for "extras":

> Optional components of a distribution may be specified using the extras field:

  identifier_end = letterOrDigit | (('-' | '_' | '.' )* letterOrDigit)
  identifier    = letterOrDigit identifier_end*
  name          = identifier
  extras_list   = identifier (wsp* ',' wsp* identifier)*
  extras        = '[' wsp* extras_list? wsp* ']'

as well as explaining their behavior, albeit briefly:

> Extras union in the dependencies they define with the dependencies of the distribution they are attached to.

The resolution on . is explained by the pip documentation[1]:

> pip looks for packages in a number of places: on PyPI (if not disabled via --no-index), in the local filesystem, and in any additional repositories specified via --find-links or --index-url. There is no ordering in the locations that are searched. Rather they are all checked, and the “best” match for the requirements (in terms of version number - see PEP 440 for details) is selected.

[0]: https://peps.python.org/pep-0508/#grammar

[1]: https://pip.pypa.io/en/stable/cli/pip_install/#finding-packa...

nprescott

4 jaar geledendiscuss

ZFS has been on my list of things I should learn "some day" for a long time. I installed Fedora a while ago and ended up opted into Btrfs without really trying. I have been pleasantly surprised with it and have used it on 2 low-impact servers and 3 personal computers for about a year.

I don't tend to do anything very interesting to tax the filesystem so it is most important that things just work day to day and the less maintenance the better. I found a few use cases[0] for the copy-on-write abilities of Btrfs (built into systemd-nspawn) after switching but even that was a case where something I was previously doing was made instantly faster rather than working out a btrfs incantation.

I've recently been trying out a nifty backup tool[1] to try out a snapshot feature locally. This one did require two btrfs specific commands to restore a backup (`btrfs {send,receive}`). Once again though, this was an additional feature I decided to try out and not really required for my day to day. For me personally Btrfs has been easy to adopt because of how low-friction it has been to add and learn incrementally.

I've still not learned ZFS.

[0]: https://idle.nprescott.com/2022/systemd-nspawn-and-btrfs.htm...

[1]: https://digint.ch/btrbk/

nprescott

4 jaar geledendiscuss

I've had success using https://git-rebase.io/ to help people understand the workflow.

nprescott

5 jaar geledendiscuss

As a specific example I routinely ran into forms that rendered like this (hidden scrollbars in three different browsers concealing content, though Safari rendered _just_ enough text that it might indicate there was more to see): https://nprescott.com/public/no-scroll-bars.png

In this specific case it is probably obvious enough that hey maybe I need to try scrolling randomly to find "baccalaureate" but the particular form that drove me to capture the above was littered with similar cases where it wasn't at all obvious. More than anything though the invisible scrollbars just meant I had to second guess every single form I ever submitted.

nprescott

5 jaar geledendiscuss

I have tried with both python 2.7.18 and python 3.8.6 using Emacs 27.1 and the excerpt works without issue for me; I have no configuration (emacs -Q) beyond pointing org to my virtual environment and allowing python evaluation in org-babel:

  (org-babel-do-load-languages 'org-babel-load-languages '((python . t)))
  (setq org-babel-python-command "~/mpl-venv/bin/python")

Are you perhaps on an outdated version of Emacs?

There have been a few different fixes around the "last line" return value over the years[0][1] but I can't really remember something like your example not working for me personally.

[0]: https://lists.gnu.org/archive/html/emacs-orgmode/2017-11/msg...

[1]: https://orgmode.org/list/[email protected]/t/#u

nprescott

5 jaar geledendiscuss

The chromium bug ticketing system is all but unreadable to me. The OP ticket itself is closed and links to another instead, is there recent movement of note?

I know igalia[0] was working on this but I haven't been following the bug trackers directly. Their site and news section gives a better sense of the progress and includes small demonstrations with many of their updates.

0: https://mathml.igalia.com/

comments