* fix: Avoid Snapshot violation
- Main thread created and "read" user
- Other thread modified something
- Main thread wants to delete or "write" to same row.
This violates snapshot isolation.
* fix: treat snapshot violation as deadlock for now
* test: handle snapshot violations
* feat: mysqlclient
* fix: update error attrs
* fix: decode mogrified query to unicode
* fix: do some cleanup
* chore: disable cleanup for now
* fix: remove unnecessary call to as_unicode
* test: skip perf test for now
* fix: fallback to empty str
* fix: unbuffered cursor support
* fix: update converters and other changes
* fix: add cleanup back
* perf: improve timedelta converter
* fix: dont attempt to run query when explain flag is set
* test: cleanup tests
* chore: remove commented code
* perf: store conf as local var
* chore: ensure sequence
---------
Co-authored-by: Ankush Menat <ankush@frappe.io>
This feels overengineered and it kinda is, but other efforts to
inroduce sequential naming/UUID naming haven't been that fruitful
either.
10 character random "hash" i now changed to.
1. first character - last character in UUID4 ID of request/job
2. three characters - derived from current timestamp.
4. 6 characters - random data.
This satisfies all three requirements:
1. Readers - temporal locality should result in spatial locality on disk. (fewer pages accessed)
2. Single writer - temporal locality should result in spatial locality. (fewer dirty pages)
3. Multiple writers - temporal locality should NOT result in spatial locality. (less lock contention)
Mostly concludes https://github.com/frappe/frappe/pull/25309 and https://github.com/frappe/frappe/pull/28349
Rough probabiliy numbers
Assumptions:
- Unique per worker prefix - 16 (uuid's base16 version)
- Rough time spent generating names - 10% of request (very very conservative estimate)
Probability(collision) = P(at least one prefix collision) * P(time collision)
Probability(collision) = (1 - p(all different)) * 10%
Probability(collision) = (1 - (16! / 16-N! )/ 16^N ) * 10%
| N (concurrency) | Probability(collision) |
| 1 | 0.0% |
| 2 | 0.6% |
| 3 | 1.8% |
| 4 | 3.3% |
| 5 | 5.0% |
| 6 | 6.6% |
| 7 | 7.9% |
| 8 | 8.8% |
* perf: faster `LocalProxy`
* refactor: use callable style local
* test: add some tests for local proxy override
---------
Co-authored-by: Ankush Menat <ankush@frappe.io>
1. It's severly outdated and free version isn't that accurate to begin
with.
2. I replaced country detection using timezone a long time ago: c8ec528aa7/frappe/desk/page/setup_wizard/setup_wizard.js (L664-L676)
This is good enough for setup wizard for most popular countries. Use
IP-API if you need better guarantees (we have a license).
Even though we never use tz aware object in frappe this function
previously used to retain them, so keep TZinfo for sake of compat.
Nothing should be affected ideally.
* perf: Reduce penalty for lack of redis connection
If redis isn't running than this client cache is slower than default
implementation because of the extra locking overhead.
* test: update perf redis counts
* perf: cache table columns in client-cache
* fix: race condition on cache-client_cache init
Rare but apparant in synthetic benchmarks.
Cache is set but client cache is still being initialized then request
will fail.
* perf: Don't run notifications when loading document
WHAT?
* fix: use cached doc to repopulate
* perf: reduce get_meta calls
