If a transfer fails for some reason, but some data managed to be sent, the
transfer will be retried. (The assistant already did this.)
Possible impacts:
* More ssh prompts if ssh needs to prompt for a password to connect to a
host, or is prompting about some other problem like a ssh key mismatch.
* More data transfer due to retrying, epecially when a remote does not
support resuming a transfer.
In the worst case, a lot of data will be transferred but it fails before
the end, and then all that data gets transferred again plus one byte more;
repeat until it manages to get the whole file.
Only done in -J mode because only if there's concurrency can downloading
from two remotes be faster. Without concurrency, it's likely the case that
sequential downloads from the same remote are faster than switching back
and forth between two remotes.
There is some hairy MVar code here, but basically it just keeps
the activeremotes MVar full except when deciding which remote to assign
to a thread.
Also affects gets by sync --content -J
This commit was sponsored by Jochen Bartl.
Note that get --from foo --failed will get things that a previous get --from bar
tried and failed to get, etc. I considered making --failed only retry
transfers from the same remote, but it was easier, and seems more useful,
to not have the same remote requirement.
Noisy due to some refactoring into Types/
Show branch:file that is being operated on.
I had to make ActionItem a type and not a type class because
withKeyOptions' passed two different types of values when using the type
class, and I could not get the type checker to accept that.
Commands that want to use it have to run their seek action inside
allowConcurrentOutput. Which seems reasonable; perhaps some future command
will want to support the -J flag but not use regions.
The region state moved from Annex to MessageState. This makes sense
organizationally, and note that some uses of onLocal use a different Annex
state, but pass the MessageState into it, which is what is needed.
* When annex objects are received into git repositories, their checksums are
verified then too.
* To get the old, faster, behavior of not verifying checksums, set
annex.verify=false, or remote.<name>.annex-verify=false.
* setkey, rekey: These commands also now verify that the provided file
matches the key, unless annex.verify=false.
* reinject: Already verified content; this can now be disabled by
setting annex.verify=false.
recvkey and reinject already did verification, so removed now duplicate
code from them. fsck still does its own verification, which is ok since it
does not use getViaTmp, so verification doesn't happen twice when using fsck
--from.
This is a work in progress. It compiles and is able to do basic command
dispatch, including git autocorrection, while using optparse-applicative
for the core commandline parsing.
* Many commands are temporarily disabled before conversion.
* Options are not wired in yet.
* cmdnorepo actions don't work yet.
Also, removed the [Command] list, which was only used in one place.
Only the assistant uses these, and only the assistant cleans them up, so
make only git annex transferkeys write them,
There is one behavior change from this. If glacier is being used, and a
manual git annex get --from glacier fails because the file isn't available
yet, the assistant will no longer later see that failed transfer file and
retry the get. Hope no-one depended on that old behavior.
This works, and seems fairly robust. Clean get of 20 files at -J3. At -J10,
there are some messages about ssh multiplexing, probably due to a race
spinning up the ssh connection cacher. But, it manages to get all the files
ok regardless.
The progress bars are a scrambled mess though, due to bugs in
ascii-progress, which I've already filed. Particularly this one:
https://github.com/yamadapc/haskell-ascii-progress/issues/8
This fixes all instances of " \t" in the code base. Most common case
seems to be after a "where" line; probably vim copied the two space layout
of that line.
Done as a background task while listening to episode 2 of the Type Theory
podcast.
Only fsck and reinject and the test suite used the Backend, and they can
look it up as needed from the Key. This simplifies the code and also speeds
it up.
There is a small behavior change here. Before, all commands would warn when
acting on an annexed file with an unknown backend. Now, only fsck and
reinject show that warning.
Motivation: Hook scripts for nautilus or other file managers
need to provide the user with feedback that a file is being downloaded.
This commit was sponsored by THM Schoemaker.
Several places assumed this would not happen, and when the AssociatedFile
was Nothing, did nothing.
As part of this, preferred content checks pass the Key around.
Note that checkMatcher is sometimes now called with Just Key and Just File.
It currently constructs a FileMatcher, ignoring the Key. However, if it
constructed a FileKeyMatcher, which contained both, then it might be
possible to speed up parts of Limit, which currently call the somewhat
expensive lookupFileKey to get the Key.
I have not made this optimisation yet, because I am not sure if the key is
always the same. Will need some significant checking to satisfy myself
that's the case..
I've been disliking how the command seek actions were written for some
time, with their inversion of control and ugly workarounds.
The last straw to fix it was sync --content, which didn't fit the
Annex [CommandStart] interface well at all. I have not yet made it take
advantage of the changed interface though.
The crucial change, and probably why I didn't do it this way from the
beginning, is to make each CommandStart action be run with exceptions
caught, and if it fails, increment a failure counter in annex state.
So I finally remove the very first code I wrote for git-annex, which
was before I had exception handling in the Annex monad, and so ran outside
that monad, passing state explicitly as it ran each CommandStart action.
This was a real slog from 1 to 5 am.
Test suite passes.
Memory usage is lower than before, sometimes by a couple of megabytes, and
remains constant, even when running in a large repo, and even when
repeatedly failing and incrementing the error counter. So no accidental
laziness space leaks.
Wall clock speed is identical, even in large repos.
This commit was sponsored by an anonymous bitcoiner.
Similar to the assistant, this honors any configured preferred content
expressions.
I am not entirely happpy with the implementation. It would be nicer if
the seek function returned a list of actions which included the individual
file gets and copies and drops, rather than the current list of calls to
syncContent. This would allow getting rid of the somewhat reundant display
of "sync file [ok|failed]" after the get/put display.
But, do that, withFilesInGit would need to somehow be able to construct
such a mixed action list. And it would be less efficient than the current
implementation, which is able to reuse several values between eg get and
drop.
Note that currently this does not try to satisfy numcopies when
getting/putting files (numcopies are of course checked when dropping
files!) This makes it like the assistant, and unlike get --auto
and copy --auto, which do duplicate files when numcopies is not yet
satisfied. I don't know if this is the right decision; it only seemed to
make sense to have this parallel the assistant as far as possible to start
with, since I know the assistant works.
This commit was sponsored by Øyvind Andersen Holm.
This is a simple approach for setting up a mirroring repository.
It will work with any type of remotes.
Mirror --from is more expensive than mirror --to in general.
OTOH, mirror --from will get the file from any remote that has it, not only
the named mirror remote. And if the named mirror remote is not the fastest
available remote with a file, that can speed things up.
It would be possible to make the assistant or watch command do a more
dynamic mirroring, that didn't need to scan every time.
Most remotes have meters in their implementations of retrieveKeyFile
already. Simply hooking these up to the transfer log makes that information
available. Easy peasy.
This is particularly valuable information for encrypted remotes, which
otherwise bypass the assistant's polling of temp files, and so don't have
good progress bars yet.
Still some work to do here (see progressbars.mdwn changes), but this
is entirely an improvement from the lack of progress bars for encrypted
downloads.
Clean up from 9769235d6b.
In some cases, looking up a remote by name even though it has no UUID is
desirable. This includes git annex sync, which can operate on remotes
without an annex, and XMPP pairing, which runs addRemote (with calls
byName) before the UUID of the XMPP remote has been configured in git.
* get/copy --auto: Transfer data even if it would exceed numcopies,
when preferred content settings want it.
* drop --auto: Fix dropping content when there are no preferred content
settings.
When a transfer fails, the progress info can be used to intelligently
retry it. If the transfer managed to make some progress, but did not
fully complete, then there's a good chance that a retry will finish it
(or at least make more progress).
Avoid crashing when "git annex get" fails to download from one location,
and falls back to downloading from a second location.
The problem is that git annex get calls download recursively from within
itself if the first download attempt fails. So the first time through, it
writes a transfer info file, which is then overwritten on the second,
recursive call. Then on cleanup, it tries to delete the file twice, which
of course doesn't work.
Fixed both by not crashing if the transfer file is removed, and by
changing Get to not run download recursively like that. It's the only
thing that did so, and it just seems like a bad idea.
In order to record a semi-useful filename associated with the key,
this required plumbing the filename all the way through to the remotes'
storeKey and retrieveKeyFile.
Note that there is potential for deadlock here, narrowly avoided.
Suppose the repos are A and B. A sends file foo to B, and at the same
time, B gets file foo from A. So, A locks its upload transfer info file,
and then locks B's download transfer info file. At the same time,
B is taking the two locks in the opposite order. This is only not a
deadlock because the lock code does not wait, and aborts. So one of A or
B's transfers will be aborted and the other transfer will continue.
Whew!
Note this is per-remote, so trying to get the same file from multiple
remotes can still let duplicate downloads run. (And uploading the same file
to multiple remotes is not duplicate at all of course.)
get, move, and copy are the only git-annex subcommands that transfer
files, but there's still git-annex-shell recvkey and sendkey to deal with too.
I considered modifying retrieveKeyFile or getViaTmp, but they are called
by other code that does not involve expensive file transfers (migrate)
or that does file transfers that should not be checked by this (fsck --from).
Now gitattributes are looked up, efficiently, in only the places that
really need them, using the same approach used for cat-file.
The old CheckAttr code seemed very fragile, in the way it streamed files
through git check-attr.
I actually found that cad8824852
was still deadlocking with ghc 7.4, at the end of adding a lot of files.
This should fix that problem, and avoid future ones.
The best part is that this removes withAttrFilesInGit and withNumCopies,
which were complicated Seek methods, as well as simplfying the types
for several other Seek methods that had a Backend tupled in.
Made --from and --to command-specific options.
Added generic storage for values of command-specific options,
which allows removing some of the special case fields in AnnexState.
(Also added generic storage for command-specific flags, although there are
not yet any.)
Note that this storage uses a Map, so repeatedly looking up the same value
is slightly more expensive than looking up an AnnexState field. But, the
value can be looked up once in the seek stage, transformed as necessary,
and passed in a closure to the start stage, and this avoids that overhead.
Still, I'm hesitant to use this for things like force or fast flags.
It's probably best to reserve it for flags that are only used by a few
commands, or options like --from and --to that it's important only be
allowed to be used with commands that implement them, to avoid user
confusion.
This new approach allows filtering out checks from the default set that are
not appropriate for a command, rather than having to list every check
that is appropriate. It also reduces some boilerplate.
Haskell does not define Eq for functions, so I had to go a long way around
with each check having a unique id. Meh.
get, drop: Added --auto option, which decides whether to get/drop content
as needed to work toward the configured numcopies.
The problem with bundling it up in optimize was that I then found I wanted
to run an optmize that did not drop files, only got them. Considered adding
a --only-get switch to it, but that seemed wrong. Instead, let's make
existing subcommands optionally smarter.
Note that the only actual difference between drop and drop --auto is that
the latter does not even try to drop a file if it knows of not enough
copies, and does not print any error messages about files it was unable to
drop.
It might be nice to make get avoid asking git for attributes when not in
auto mode. For now it always asks for attributes.
The only remaining vestiage of backends is different types of keys. These
are still called "backends", mostly to avoid needing to change user interface
and configuration. But everything to do with storing keys in different
backends was gone; instead different types of remotes are used.
In the refactoring, lots of code was moved out of odd corners like
Backend.File, to closer to where it's used, like Command.Drop and
Command.Fsck. Quite a lot of dead code was removed. Several data structures
became simpler, which may result in better runtime efficiency. There should
be no user-visible changes.
get not honoring --from has surprised me a few times, so least surprise
suggests it should just behave like copy --from. This leaves the difference
between get and copy being that copy always requires the remote to copy
from, while get will decide whether to get a file from a key/value store or
a remote.
