match_continuous limits the search to the current start position,
instead of searching the entire file.
On libc++, this improves performance dramatically:
$ time /nix/store/70ai68dfm6xbzwn26j5n4li9di52ylia-nix-3.0pre20200728_c159f48/bin/nix print-dev-env >/dev/null
/nix/store/70ai68dfm6xbzwn26j5n4li9di52ylia-nix-3.0pre20200728_c159f48/bin/ni 2.39s user 0.19s system 64% cpu 4.032 total
$ time /nix/store/cwjfxxlp83zln4mfyy1d2dbsx7f6s962-nix-3.0pre20200728_dirty/bin/nix print-dev-env >/dev/null
/nix/store/cwjfxxlp83zln4mfyy1d2dbsx7f6s962-nix-3.0pre20200728_dirty/bin/nix 0.09s user 0.05s system 65% cpu 0.204 total
Fixes#3874
Since 6185d25e52, this was very
latency-bound since it required a round-trip for every 32 KiB. So for
example copying a 514 MiB closure over a virtual ethernet device with
a articial delay of just 1 ms took 343s. Now it takes 2.7s.
Fixes#3372.
If a repo is dirty, it used to return a `rev` object with an "empty"
sha1 (0000000000000000000000000000000000000000). Please note that this
only applies for `builtins.fetchGit` and *not* for `builtins.fetchTree{
type = "git"; }`.
istream->tellg() returns -1 so we can't get the number of bytes
written.
Fixes 'uploaded 's3://nix-cache/nar/00819r9lp5kajr6baxfw5dhhc0cx8ndxaz43qmd2f0gn1hk1ynlp.nar.xz' (-1 bytes) in 11620 ms' messages.
The original idea was to implement a git-fetcher in Nix's core that
supports content hashes[1]. In #3549[2] it has been suggested to
actually use `fetchTree` for this since it's a fairly generic wrapper
over the new fetcher-API[3] and already supports content-hashes.
This patch implements a new git-fetcher based on `fetchTree` by
incorporating the following changes:
* Removed the original `fetchGit`-implementation and replaced it with an
alias on the `fetchTree` implementation.
* Ensured that the `git`-fetcher from `libfetchers` always computes a
content-hash and returns an "empty" revision on dirty trees (the
latter one is needed to retain backwards-compatibility).
* The hash-mismatch error in the fetcher-API exits with code 102 as it
usually happens whenever a hash-mismatch is detected by Nix.
* Removed the `flakes`-feature-flag: I didn't see a reason why this API
is so tightly coupled to the flakes-API and at least `fetchGit` should
remain usable without any feature-flags.
* It's only possible to specify a `narHash` for a `git`-tree if either a
`ref` or a `rev` is given[4].
* It's now possible to specify an URL without a protocol. If it's missing,
`file://` is automatically added as it was the case in the original
`fetchGit`-implementation.
[1] https://github.com/NixOS/nix/pull/3216
[2] https://github.com/NixOS/nix/pull/3549#issuecomment-625194383
[3] https://github.com/NixOS/nix/pull/3459
[4] https://github.com/NixOS/nix/pull/3216#issuecomment-553956703
It's a tiny function which is:
- hardly worth abstrating over, and also only used once.
- doesn't work once we get CA drvs
I rewrote the one callsite to be forwards compatable with CA
derivations, and also potentially more performant: instead of reading in
the derivation it can ust consult the SQLite DB in the common case.
Currently resizing of the terminal doesn't play nicely with
nix edit when using kakoune as the editor, as it relies on the
SIGWINCH signal which is trapped by nix. How this is not a problem
with e.g. vim is beyond me.
Virtually all other exec* calls are following a call to
restoreSignals(). This commit adds this behavior to nix edit
as well.
Maximilian Bosch