5 ms·

The point is that ripgrep will give you basically all the same query features just by being fast. A more structured format makes sense, but the indexing is not

by rcxdude 2mo ago

The point is that ripgrep will give you basically all the same query features just by being fast. A more structured format makes sense, but the indexing is not obviously adding value in most cases.

otterley 2mo ago
The difference between grep/ripgrep and querying by field is the difference between a full table scan and an index query. Query performance is a very good reason to have databases. ripgrep is certainly fast, but it's still O(N). Doing complete file scans also trashes the OS's buffer cache.
- brohee 2mo ago
  Writing multiple pages for a few hundred actual bytes also thrashes the OS cache...
  - otterley 2mo ago
    Not if you use the correct cache hint flags on the write.
- pineapplepizza6 2mo ago
  [dead]
- VGHN7XDuOXPAzol 2mo ago
  I really want to love journald (it sounds like it's aiming for a good system) but I share the other commenter(s)' frustration here about journald being slower than just pulling out ripgrep on regular files. We have some services at work that log to text files and some to journald. The log volume to file is >> the log volume to journald. Yet `rg query myservice.2026-08-01.log` seems to always wind up being faster and better than something like `journalctl -u myservice.service --since '2026-08-01' --until '2026-08-02' -g 'query'`. (The tab completion and discoverability is also better, I guess)
  - otterley 2mo ago
    What do the metrics look like in practice? seems is a bit too handwavy. I get that impressions matter, but data is actionable.
    - bombela 2mo ago
      I have been complaining about journald abysmal performances for almost as long as I can remember. Here is my latest documented benchmark from 2023, which was slightly better than the one I ran in 2020. $ time journalctl > /tmp/all.log real 1m11.364s user 0m52.299s sys 0m6.540s $ time wc -l /tmp/all.log 3659597 /tmp/all.log real 0m0.152s user 0m0.056s sys 0m0.096s $ time journalctl | grep sshd | wc -l 12944 real 0m53.973s user 0m49.535s sys 0m5.210s $ time grep sshd /tmp/all.log | wc -l 12944 real 0m0.429s user 0m0.332s sys 0m0.100s https://github.com/systemd/systemd/issues/2460#issuecomment-1577671723 https://github.com/systemd/systemd/issues/2460#issuecomment-...
      - marginalia_nu 2mo ago
        I'm no fan of journald, but I have some methodological issues with this test. The reads from /tmp/all.log are almost certainly cached since you just wrote the file, and will basically boil down to a memcpy call, rather than actual disk I/O. Speed difference isn't as big as you would think on a modern SSD, but it isn't nothing either. Running this between calls should flush the changes to disk and then drop the page cache, making for a fairer test. $ sudo sync $ echo 3 | sudo tee /proc/sys/vm/drop_caches
        soneil 2mo ago
        I tried similar. Each command looped 5 times, ignore the best and worst times, and average the mean three. journalctl >/tmp/all.log 0m59.763s journalctl | grep -c sshd 0m57.767s (otherwise >all is the only example encumbered by write speeds) wc -l /tmp/all.log 0m0.336s grep -c sshd /tmp/all.log 0m1.776s

by rcxdude 2mo ago

The point is that ripgrep will give you basically all the same query features just by being fast. A more structured format makes sense, but the indexing is not obviously adding value in most cases.

otterley 2mo ago

The difference between grep/ripgrep and querying by field is the difference between a full table scan and an index query. Query performance is a very good reason to have databases. ripgrep is certainly fast, but it's still O(N). Doing complete file scans also trashes the OS's buffer cache.

brohee 2mo ago
Writing multiple pages for a few hundred actual bytes also thrashes the OS cache...
- otterley 2mo ago
  Not if you use the correct cache hint flags on the write.
pineapplepizza6 2mo ago
[dead]
VGHN7XDuOXPAzol 2mo ago
I really want to love journald (it sounds like it's aiming for a good system) but I share the other commenter(s)' frustration here about journald being slower than just pulling out ripgrep on regular files. We have some services at work that log to text files and some to journald. The log volume to file is >> the log volume to journald. Yet `rg query myservice.2026-08-01.log` seems to always wind up being faster and better than something like `journalctl -u myservice.service --since '2026-08-01' --until '2026-08-02' -g 'query'`. (The tab completion and discoverability is also better, I guess)
- otterley 2mo ago
  What do the metrics look like in practice? seems is a bit too handwavy. I get that impressions matter, but data is actionable.
  - bombela 2mo ago
    I have been complaining about journald abysmal performances for almost as long as I can remember. Here is my latest documented benchmark from 2023, which was slightly better than the one I ran in 2020. $ time journalctl > /tmp/all.log real 1m11.364s user 0m52.299s sys 0m6.540s $ time wc -l /tmp/all.log 3659597 /tmp/all.log real 0m0.152s user 0m0.056s sys 0m0.096s $ time journalctl | grep sshd | wc -l 12944 real 0m53.973s user 0m49.535s sys 0m5.210s $ time grep sshd /tmp/all.log | wc -l 12944 real 0m0.429s user 0m0.332s sys 0m0.100s https://github.com/systemd/systemd/issues/2460#issuecomment-1577671723 https://github.com/systemd/systemd/issues/2460#issuecomment-...
    - marginalia_nu 2mo ago
      I'm no fan of journald, but I have some methodological issues with this test. The reads from /tmp/all.log are almost certainly cached since you just wrote the file, and will basically boil down to a memcpy call, rather than actual disk I/O. Speed difference isn't as big as you would think on a modern SSD, but it isn't nothing either. Running this between calls should flush the changes to disk and then drop the page cache, making for a fairer test. $ sudo sync $ echo 3 | sudo tee /proc/sys/vm/drop_caches
      - soneil 2mo ago
        I tried similar. Each command looped 5 times, ignore the best and worst times, and average the mean three. journalctl >/tmp/all.log 0m59.763s journalctl | grep -c sshd 0m57.767s (otherwise >all is the only example encumbered by write speeds) wc -l /tmp/all.log 0m0.336s grep -c sshd /tmp/all.log 0m1.776s