We are currently using libsqlite3-sys 0.25.2,
corresponding to SQLcipher 4.5.2
and SQLite 3.39.2.
SQLite supports ALTER TABLE DROP COLUMN since version 3.35.0,
and it has received critical database corruption bugfixes in 3.35.5.
There have been no fixes to it between SQLite 3.36.0 and 3.41.0,
so it appears stable now.
We do not make all transactions
[IMMEDIATE](https://www.sqlite.org/lang_transaction.html#deferred_immediate_and_exclusive_transactions)
for more parallelism -- at least read transactions can be made DEFERRED to run in parallel
w/o any drawbacks. But if we make write transactions DEFERRED also w/o any external locking,
then they are upgraded from read to write ones on the first write statement. This has some
drawbacks:
- If there are other write transactions, we block the thread and the db connection until
upgraded. Also if some reader comes then, it has to get next, less used connection with a
worse per-connection page cache.
- If a transaction is blocked for more than busy_timeout, it fails with SQLITE_BUSY.
- Configuring busy_timeout is not the best way to manage transaction timeouts, we would
prefer it to be integrated with Rust/tokio asyncs. Moreover, SQLite implements waiting
using sleeps.
- If upon a successful upgrade to a write transaction the db has been modified by another
one, the transaction has to be rolled back and retried. It is an extra work in terms of
CPU/battery.
- Maybe minor, but we lose some fairness in servicing write transactions, i.e. we service
them in the order of the first write statement, not in the order they come.
The only pro of making write transactions DEFERRED w/o the external locking is some
parallelism between them. Also we have an option to make write transactions IMMEDIATE, also
w/o the external locking. But then the most of cons above are still valid. Instead, if we
perform all write transactions under an async mutex, the only cons is losing some
parallelism for write transactions.
scripts/update-provider-database.sh checks out the provider database
and updates data.rs file,
making it easier to update.
CI uses this script to check that checked in data.rs
corresponds to the provider database repository.
This makes DC compatible with "multipart/signed" messages thus allowing switching to them someday
from the current "multipart/mixed" unencrypted message format.
try_decrypt() is a CPU-bound task.
When called from async function,
it should be wrapped in tokio::task::spawn_blocking().
Using tokio::task::spawn_blocking() is difficult here
because of &mail, &private_keyring and &public_keyring borrows,
so we should at least use tokio::task::block_in_place()
to avoid blocking the executor.
Previously we used tags like "1.109.0" and "py-1.109.0".
Since Python bindings are always released
at the same time as the core,
it is easier to use a single tag for them.
"v" prefix is added to make matching by "v*" easier
in CI and scripts.
the speedup of #4065 is larger than measured first
running `cargo test`, first we thought there is only a slight speedup
from 13.5 seconds to 12.5 seconds on a m1pro.
however, there is one test that does 11 seconds of sleep() (test_modify_chat_disordered)
as this test is not run very first, this slows down things overall.
skipping this test,
speedup is from 13.5 seconds to 9.5 seconds -
28% faster - and this is something we should mention in the changelog :)
(this pr does not remove or change the slow test.
i think, due to the number of cores, this is not needed until someone
has a machine where the other tests run in 2 seconds or so)
.call() interface is safer because it ensures
that blocking operations on SQL connection
are called within tokio::task::block_in_place().
Previously some code called blocking operations
in async context, e.g. add_parts() in receive_imf module.
The underlying implementation of .call()
can later be replaced with an implementation
that does not require block_in_place(),
e.g. a worker pool,
without changing the code using the .call() interface.
Gmail archives messages marked as `\Deleted` by default if those messages aren't in the Trash. But
if move them to the Trash instead, they will be auto-deleted in 30 days.
With the introduction of transactions in Contact::add_or_lookup(),
python tests sometimes fail to create contacts with the folowing error:
Cannot create contact: add_or_lookup: database is locked: Error code 5: The database file is locked
`PRAGMA busy_timeout=60000` does not affect
this case as the error is returned before 60 seconds pass.
DEFERRED transactions with write operations need
to be retried from scratch
if they are rolled back
due to a write operation on another connection.
Using IMMEDIATE transactions for writing
is an attempt to fix this problem
without a retry loop.
If we later need DEFERRED transactions,
e.g. for reading a snapshot without locking the database,
we may introduce another function for this.
When connection pool is organized as a stack,
it always returns most recently used connection.
Because each connection has its own page cache,
using the connection with fresh cache improves performance.
I commented out `oauth2::tests::test_oauth_from_mx`
because it requires network connection,
turned off the Wi-Fi and ran the tests.
Before the change, with a queue:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 56.424 s ± 4.515 s [User: 183.181 s, System: 128.156 s]
Range (min … max): 52.123 s … 68.193 s 10 runs
```
With a stack:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 29.887 s ± 1.377 s [User: 101.226 s, System: 45.573 s]
Range (min … max): 26.591 s … 31.010 s 10 runs
```
On version 1.107.1:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 43.658 s ± 1.079 s [User: 202.582 s, System: 50.723 s]
Range (min … max): 41.531 s … 45.170 s 10 runs
```
* jsonrpc: `get_messages` now returns a map with `MessageLoadResult`
instead of failing completely if one of the requested messages could not be loaded.
* add pr number to changelog
* format errors with causes instead of debug output
also for chatlistitemfetchresult