We use relaxed ordering in a lot of places where we really need to
ensure all CPUs see the write. Switch to sequential consistency, unless
acquire/release is explicitly used. If there are places that can be
optimized, we can switch to relaxed case-by-case, but have a comment
explaning *why* it is safe.
Closes#3193
We use relaxed ordering in a lot of places where we really need to
ensure all CPUs see the write. Switch to sequential consistency, unless
acquire/release is explicitly used. If there are places that can be
optimized, we can switch to relaxed case-by-case, but have a comment
explaning *why* it is safe.
Currently header changes are tracked through pager by reading page 1.
MVCC has it's own layer to track changes during txn so this commit makes
it so that headers are tracked by each txn separately.
On commit we update the _global_ header which is used to update
`database_size` because pager commits require it to be up to date. This
also makes it _simpler_ to keep track of header updates and update
pager's header accordingly.
This PR is needed in order to make logical log work because we don't
want to rely on pager as much as possible!
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Closes#3156
Currently header changes are tracked through pager by reading page 1.
MVCC has it's own layer to track changes during txn so this commit makes
it so that headers are tracked by each txn separately.
On commit we update the _global_ header which is used to update
`database_size` because pager commits require it to be up to date. This
also makes it _simpler_ to keep track of header updates and update
pager's header accordingly.
this is only used for returning LimboResult::Busy, and we already
have LimboError::Busy, so it only adds confusion.
Moreover, the current busy handler was not handling LimboError::Busy,
because it's returned as an error, not as Ok. So this may fix the
"busy handler not working" issue in the perf thrpt benchmark.
This PR extends the existing encryption support to include the database
header page (page 1).
Reviewed-by: Avinash Sajjanshetty (@avinassh)
Closes#3040
This adds basic support for window functions. For now:
* Only existing aggregate functions can be used as window functions.
* Specialized window-specific functions (`rank`, `row_number`, etc.) are
not yet supported.
* Only the default frame definition is implemented:
`RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW EXCLUDE NO OTHERS`.
Reviewed-by: Jussi Saurio <jussi.saurio@gmail.com>
Reviewed-by: Preston Thorpe <preston@turso.tech>
Closes#3079
current logic can lead to a situation where:
- we call read_page(trunk_page_id)
- we assign trunk_page in the FreePageState state machine
- the page read fails and cache marks it as !locked && !loaded
- next call to Pager::free_page() asserts that the page is loaded and panics
Based on #3126Closes#3029Closes#3030Closes#3065Closes#3083Closes#3084Closes#3085
simple reason why mvcc update didn't work: it didn't try to update.
Closes#3127
This patch adds checksums to Turso DB. You may check the design here in
the [RFC](https://github.com/tursodatabase/turso/issues/2178).
1. We use reserved bytes (8 bytes) to store the checksums. On every IO
read, we verify that the checksum matches.
2. We use twox hash for checksums.
3. Checksum works only on 4K pages now. It's a small change to enable
for all other sizes, I will send another PR.
4. Right now, it's not possible to switch to different algorithm or turn
off altogether. That will be added in the future PRs.
5. Checksums can be enabled only for new dbs. For existing DBs, we will
disable it.
6. To add checksums for existing DBs, we need vacuum since it would
require rewrite of whole db.
Closes#2840
