Zstd java jni

Bullshit, Zstd was open-source from the very beginning, they just hired Yann and moved the project under facebook org. How do I know? I have written the JVM bindings [1] since v0. EDIT: Actually, my initial bindings were against v0.

This is just a PR false claim.

zstd java jni

Given that it was Yann himself who wrote that sentence, I think that's a needlessly uncharitable interpretation. Maybe a better wording would have been "Two years ago, we released Zstandard v1.

But I don't think we anticipated anyone would read that much into it. Blog posts from companies are always reviewed by the marketing team, that frequently changes what the author initially wrote, or adds random stuff to make it sound more like a company effort.

This also seemed to me like one of those "team effort", "good job, guys" surreptitious edits. Yes, may be I read it the wrong way. I later noticed the authors. BTW, thank you for your part at making it the best compression library for wide variaty of cases. Thank you for helping build an ecosystem around Zstd! Previously the license was BSD as my commit above shows. After concerns from the community the patent clause was dropped, a little bit after React.

JNI API Usage in Linux Environment

JyrkiAlakuijala on Dec 20, With internet speed significantly above the decompression speeds zstd is favorable. With internet speeds below the decompression speeds brotli is favorable because less bytes need to be transmitted. It is also not just about speed, but mobile users need to pay less with brotli as less bytes are transferred. Further I'm not an expert on this, somewhat speculative but likely the streaming properties of brotli are slightly better, i.

This may allow the browser to issue new fetches for urls in an html document earlier with brotli than with zstd. From what you say, it sounds like you think, that Brotli has a better compression ratio, than Zstdandard. It is a cherry picked data point, and not representative for brotli. There, facebook shows numbers with quality 0. However, when they compress for the web, they use brotli with quality 5 for dynamic content and quality 9 or 11? At higher quality settings brotli wins in compression density, and particularly so with quality 11 or with short files.

Quality 0 is an irrelevant corner case of maximal compression speed, and is completely impractical for most uses. You shouldn't dismiss compression speeds and hardware requirements though, as not all content in the internet is static. It's something we're actively working on! Brotli is a competitor of zstd from Google. Google integrated Brotli into Chrome. Facebook are trying to get zstd into Chrome.

I hope they pay greater attention to the low and high end of their compression ratio spectrum. On the low end, it'd be great if it could exceed lz4 in terms of speed and memory savings. Right now it's impressive "in the middle", but I find myself in a lot of situations where I care about the extremes.

It does depend on your dataset. However, the massive improvement in decompression speed is what won me over.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. There is some information via strings and string arrays that I need to pass to the Java application via JNI.

I did find the following code from here. But this makes no sense to me. Is the code sending out the message upon execution of the return ret ; line? Or during the execution of the line within for loop? Will the code I found work for what I want with some adaptation? Is what I am looking for even possible? If so, how can I do it? That being said. The code I am working on is for an IM client that will need to push message and presence updates to the Android java application via JNI so that the Android application does not poll for updates.

I have managed to learn how to setup the functions for the java code to call to requrest information. However, I do not have any idea how to push new message or presence information jabber stanza strings to the java code when it comes in.

All the code that I have seen on how to do this see below for example seems to require getting information from the java code env, class, methodid, etc. Only when you return it will your java app get access to it. Pass a String array to your native function. This will probably be pointless since you end up having to call a function which I persume you do not want. I dont know how you will signal your java code that the field has been updated though if you need it.

EDIT The updated function which you have written is meant to be called from the java layer.

zstd java jni

To call java code from a native context, you will need references to the env and obj from java. You will also probably have to look up how to use global references in JNI. At the request of Sam, here is a method that avoids using modified UTF-8 because we don't know that it is safe to do so. It is not correct to use it with user data--it's unlikely to be encoded with modified UTF We could just hope that the characters in the data are restricted to keep it compatible.

Instead, we can convert it properly. We can use strings we know are compatible, particularly literals for Java identifiers except not all currency symbols.How does zstd compare with brotli? Would it be a better compression standard for http responses? For what it's worth from my not-particularly-scientific tests at work, they both compressed significantly better than gzip, but zstd compressed better and faster than brotli for our typical file sizes text files around kb. Unfortunately, we have a strict requirement that the decompression be done in pure Java and ideally providing an InputStream interface.

The official Brotli repo includes a pure Java decompression library that took about three lines of code to drop in next to our gzip support, while zstd had nothing suitable a JNI wrapper is not an option, and the Java decompressor at [1] does not provide an streaming interface. Writing my own Java decompressor for zstd sounded like a fun project, but that would have been too much like yak shaving; brotli is good enough. JyrkiAlakuijala on Dec 19, Even the zstd folks themselves fell into the trap of comparing brotli and zstd with different window sizes.

zstd java jni

I never was able to locate a file that compresses better with zstd than with brotli, if you use the same window size in both. The car analogy in using different window sizes is to drive on 1st gear with one car and drive on 5th gear with other, i. One needs to use the same window size with both algos to be able to understand the performance potential in them. When one does that, brotli always wins in density and most of the time on compression speed to a given density. They compare pretty closely.

The squash benchmark is a nice interactive comparison tool that usually agrees with my own benchmarks. See for example [1]. Note that you should experiment with different input texts to get a sense for the variability in relative performance.

I am working on that very question! Zstd's support for creating and using custom dictionaries opens the door to significant efficiencies. As described in the post though, dictionaries make compression a more complicated thing to use, and so there are lots of questions about how to apply that to the public internet in a way that's cross-compatible and secure. In short: it's something we're actively exploring. Brotli added custom dictionaries in or before zstd format was even frozen.

Browsers could cache dictionaries per MIME type per domain which are provided by the server. Would be super cool, if a bit more complicated. Yep, that's in the vicinity of the solutions we're thinking about. There are a few proposals out there, and prior art like SDCH [1]. The hard part is that compression is already an attack vector for the web e.

We want to make sure that we're not eroding or unduly complicating that situation [4]. Both brotli and zstd support user-provided dictionaries, which helps with compressing files which contain items from the dictionary.

This is particularly helpful for small files. Zstd is both faster and more effective at compressing. If you compress to same density, brotli tends to be significantly faster. Zstd decompresses faster.

Brotli is naturally limited to 16 MB of memory use whereas ZStd makes less attempts to reduce memory use. Without it, zstd memory usage will be limited to 8 MB. It has been there since, forever. JyrkiAlakuijala on Dec 20, Levels above 19, which has a 8 MB window size, may only be used with the --ultra flag, whose documentation says "requires more memory".

Brotli separates out the window size from the quality, but in zstd the level implies the window size, unless you use advanced parameters. For example, level 3 has a 1 MB window size.GitHub is home to over 50 million developers working together to host and review code, manage projects, and build software together. We use optional third-party analytics cookies to understand how you use GitHub. Learn more. You can always update your selection by clicking Cookie Preferences at the bottom of the page.

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Sign up. Go to file T Go to line L Copy path. Latest commit bbeb Jul 21, History. Raw Blame. ByteBuffer ; import java. Arrays ; import com. Native ; import com. ZstdCompressCtx ; import com. You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window.

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ZstdCompressorOutputStream.java

Analytics cookies We use analytics cookies to understand how you use our websites so we can make them better, e. Save preferences. ByteBuffer.

Arrays. Native. ZstdCompressCtx. ZstdDecompressCtx. Worst case size evaluation is provided by function.

zstd java jni

It is assumed that the position of this buffer marks the offset.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Learn more. Questions tagged [java-native-interface]. Ask Question. Learn moreā€¦ Top users Synonyms 1. Filter by. Sorted by. Tagged with. Apply filter. I am trying to copy a jintArray passed into my function into a new int[] array. However, I keep getting errors when I try to create the int array. The code with which I attempted to solve this Entering JNI again on a thread executing native code [closed] I have a Kotlin callback passed to native code which fires the callback via AttachCurrentThread from time the time, it's work without issue.

However, if I enter JNI again from within the callback I have used a hello world example to attempt to get an idea of how this works. Right now, when I run the Java Nitrogen 11 2 2 bronze badges. I get a linkage error to functions which are defined within jni. Diversity 1, 10 10 silver badges 19 19 bronze badges.

Virudhai Paul 39 6 6 bronze badges. Then the Rust project itself is cross compiled to a static and a dynamic library for different Ali Somay 5 5 silver badges 15 15 bronze badges.

Nick 3, 2 2 gold badges 24 24 silver badges 40 40 bronze badges. I have an app that uses JNI to invoke java from Rust.

Right now I am initializing the JVM with a classpath that is hardcoded to a large number of jar files in a tree under my home directory they Mutant Bob 1, 1 1 gold badge 15 15 silver badges 33 33 bronze badges. I need to be able to feed C an array of double from Java, run the filter, Guerlando OCs 5 5 silver badges 16 16 bronze badges. ErrnoException: chmod Z 1 2 2 bronze badges.Discussion thread : thread1 thread2.

Please keep the discussion on the mailing list rather than commenting on the wiki wiki discussions get unwieldy fast. With its great performance in both speed and compression rate, lots of popular big data processing frameworks are supporting ZStandard. ZStandard also works well with Apache Kafka. Benchmarks with the draft version with ZStandard 1. The following benchmark is based on Shopify's production environment Thanks to bobrik. As You can see, ZStandard outperforms with a compression ratio of 4.

It is worth noting that this outcome is based on ZStandard 1. According to Facebook, ZStandard 1. It's id will be 4. For details on this error code, see 'Compatibility, Deprecation, and Migration Plan' section. You can check the concept-proof implementation of this feature on this Pull Request. We need to establish some backward-compatibility strategy for the case an old client subscribes a topic using ZStandard, explicitly or implicitly i.

After discussion, we decided to support zstd to the new clients only i. Zstd will only be allowed for the bumped fetch API. This strategy necessarily requires the down-conversion of v2 message compressed with Zstandard into v0 or v1 messages, which means a considerable performance degradation.

So we rejected this strategy. With this approach, we can message the old clients that they are old and should be upgraded. However, there are still several options for the Error code. This option gives the client so little information; the user can be confused about why the client worked correctly in the past suddenly encounters a problem. This option gives inaccurate information; the user can be surprised and misunderstand that the log files are broken in some way.

Download java-util JAR file with all dependencies

The advantage of this approach is that we don't need to define a new error code; we can reuse it and that's all. The disadvantage of this approach is that it is also a little bit vague; This error code is defined as a work for KIP and now returned in the transaction error. Since adding a new error type is not a big problem and a clear error message always helps, we decided to reject this strategy.I am getting better throughput by using Channels than I do by using Streams and we need this to be a very high throughput system as we need to process 40 TB of files every day and this part of the process is currently the bottleneck.

The files are compressed with zstd-jni. Zstd-jni has api's for decompressing byte buffers but I get an error when I use them.

How do I decompress large files using Zstd-jni and Byte Buffers

How do I decompress a byte buffer at a time using zstd-jni? Below is my code for compressing and decompressing files. The compression code works great, but the decompression code then fails with an error of I'm currently trying to integrate some Java code with a Watson Conversation Dialog.

At the moment, I'm using the following code to pass a simple text input to the Watson dialog: MessageRequest How to compare name of an object to a string in Java? What is the correct way to do that?

I am using jexcel api in java. I need to read xls paticular column value and have to sort the entire rows in xls based on that. Then I have to save those rows in sorted manner in new xls. I able to do It was claimed that The two bimaps are backed by the same data; any changes to one will appear in the other. I browsed through the How do I decompress large files using Zstd-jni and Byte Buffers. Compare object name reference name with a string. I have to sort xls sheet rows using a column values in java using jexcel.

Essence of BiMap in Google collections.


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