Comments (4)
kszlim
commented on August 15, 2024
Not really a bug (nor is this really a feature request?). Perhaps there isn't much improvement to be made?
from polars.
ritchie46
commented on August 15, 2024
I look at the profile of this. This is all thrift decoding the metadata. Which is a known flaw of parquet.
from polars.
kszlim
commented on August 15, 2024
@ritchie46 but I'd at least expect all my CPU cores to be pinned, but it appears to almost be single threaded? The metadata per file should be individually parseable right?
from polars.
kszlim
commented on August 15, 2024
Looks like arrow-rs apache/arrow-rs#5853 has been investigating this issue, maybe parquet v3 will also help fix this flaw.
from polars.
Related Issues (20)
- Polars use nest_asyncio
- Cannot scan cloud files containing spaces in path name HOT 8
- DataFrame rename method is extremely slow for dictionary argument
- Support for Business Day Lengths in group_by_dynamic
- Support for making all possible combinations of elements in a df, multiIndex from the cartesian product of multiple iterables? HOT 2
- Slow rolling_skew performance and inconsistent signature vs other rolling methods HOT 1
- sum() and cum_sum() do not cast to UInt64 when data overflows UInt32 HOT 3
- Support casting String to Time HOT 5
- `pl.col('str_col').cast(pl.UInt8).fill_null(pl.lit(0))` gets converted to Int16 type HOT 4
- add `with_source_column` to `scan_parquet` and `read_parquet`
- Rolling_mean with weights gives wrong result when min_periods is not None HOT 1
- json_decode with majority-null columns often fails schema unification HOT 4
- ComputeError: parquet: File out of specification: Invalid thrift: protocol error HOT 2
- List(string) cannot be coerced with String anymore since 1.0 in Concat HOT 2
- Support `Decimal` in `read_csv` HOT 3
- `pl.struct` named expr combined with `.name.keep()` PanicException
- pl.col() mixes strangely with selectors HOT 3
- LazyFrame OOM on CSVs with rows that contains large amount of data HOT 2
- `pl.from_pandas` with columns that mix strings and NAs results in `TypeError` HOT 3
- ComputeError: this expression cannot run in the group_by context HOT 1
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from polars.