Tag - performance

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2020-06-05

SQlite3 Encryption Not Possible Any More Since 3.32.x

About latest SQlite3 3.32.xxx there is a big problem with codecs.

Critical changes to the public SQLite code were introduced on Feb 7, 2020: “Simplify the code by removing the unsupported and undocumented SQLITE_HAS_CODEC compile-time option”. With the release of SQLite version 3.32.0 on May 22, 2020 these changes finally took officially effect, although they weren't officially announced.

As a sad and unexpected consequence, we are NOT ANY MORE able to compile the new SQlite3 amalgamation with our encryption patch.

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2020-05-07

New Multi-thread Friendly Memory Manager for FPC written in x86_64 assembly

As a gift to the FPC community, I just committed a new Memory Manager for FPC.
Check mormot.core.fpcx64mm.pas in our mORMot2 repository.
This is a stand-alone unit for FPC only.

It targets Windows and Linux multi-threaded Service applications - typically mORMot daemons.
It is written in almost pure x86_64 assembly, and some unique tricks in the Delphi/FPC Memory Manager world.

It is based on FastMM4 (not FastMM5), and we didn't follow the path of the FastMM4-AVX version - instead of AVX, we use plain good (non-temporal) SSE2 opcode, and we rely on the mremap API on Linux for very efficient reallocation. Using mremap is perhaps the biggest  benefit of this memory manager - it leverages a killer feature of the Linux kernel for sure. By the way, we directly call the Kernel without the need of the libc.

We tuned our x86_64 assembly a lot, and made it cross-platform (Windows and POSIX). We profiled the multi-threading, especially by adding some additional small blocks for GetMem (which is a less expensive notion of "arenas" as used in FastMM5 and most C allocators), introducing an innovatice and very efficient round-robin of tiny blocks (<128 bytes), and proper spinning for FreeMem and medium blocks.

It runs all our regression tests with huge performance and stability - including multi-threaded tests with almost no slow down: sleep is reported as less than 1 ms during a 1 minute test. It has also been validated on some demanding multi-threaded tasks.

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2020-03-28

Faster Double-To-Text Conversion

On server side, a lot of CPU is done processing conversions to or from text. Mainly JSON these days.

In mORMot, we take care a lot about performance, so we have rewritten most conversion functions to have something faster than the Delphi or FPC RTL can offer.
Only float to text conversion was not available. And RTL str/floattexttext performance, at least under Delphi, is not consistent among platforms.
So we just added a new Double-To-Text set of functions.

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2020-02-17

New move/fillchar optimized sse2/avx asm version

Our Open Source framework includes some optimized asm alternatives to RTL's move() and fillchar(), named MoveFast() and FillCharFast().

We just rewrote from scratch the x86_64 version of those, which was previously taken from third-party snippets.
The brand new code is meant to be more efficient and maintainable. In particular, we switched to SIMD 128-bit SSE2 or 256bit AVX memory access (if available), whereas current version was using 64-bit regular registers. The small blocks (i.e. < 32 bytes) process occurs very often, e.g. when processing strings, so has been tuned a lot. Non temporal instructions (i.e. bypassing the CPU cache) are used for biggest chunks of data. We tested ERMS support, but it was found of no benefit in respect to our optimized SIMD, and was actually slower than our non-temporal variants. So ERMS code is currently disabled in the source, and may be enabled on demand by a conditional.

FPC move() was not bad. Delphi's Win64 was far from optimized - even ERMS was poorly introduced in latest RTL, since it should be triggered only for blocks > 2KB. Sadly, Delphi doesn't support AVX assembly yet, so those opcodes would be available only on FPC.

Resulting numbers are talking by themselves. Working on Win64 and Linux, of course.

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2018-11-12

EKON 22 Slides and Code

I've uploaded two sets of slides from my presentations at EKON 22 : Object Pascal Clean Code Guidelines Proposal High Performance Object Pascal Code on Servers with the associated source code The WorkShop about "Getting REST with mORMot" has a corresponding new Samples folder in our  […]

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2018-03-12

New AES-based SQLite3 encryption

We just committed a deep refactoring of the SynSQlite3Static.pas unit - and all units using static linking for FPC. It also includes a new encryption format for SQlite3, using AES, so much more secure than the previous one. This is a breaking change, so worth a blog article! Now all static .o .a  […]

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2018-02-07

Status of mORMot ORM SOA MVC with FPC

In the last weeks/months, we worked a lot with FPC.
Delphi is still our main IDE, due to its better debugging experience under Windows, but we target to have premium support of FPC, on all platforms, especially Linux.

The new Delphi Linux compiler is out of scope, since it is heavily priced, its performance is not so good, and ARC broke memory management so would need a deep review/rewrite of our source code, which we can't afford - since we have FPC which is, from our opinion,  a much better compiler for Linux.
Of course, you can create clients for Delphi Linux and FMX, as usual, using the cross-platform client parts of mORMot. But for server side, this compiler is not supported, and will probably never be.

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2016-04-09

AES-256 based Cryptographically Secure Pseudo-Random Number Generator (CSPRNG)

Everyone knows about the pascal random() function.
It returns some numbers, using a linear congruential generator, with a multiplier of 134775813, in its Delphi implementation.
It is fast, but not really secure. Output is very predictable, especially if you forgot to execute the RandSeed() procedure.

In real world scenarios, safety always requires random numbers, e.g. for key/nonce/IV/salt/challenge generation.
The less predictable, the better.
We just included a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG) into our SynCrypto.pas unit.
The TAESPRNG class would use real system entropy to generate a sequence of pseudorandom bytes, using AES-256, so returning highly unpredictable content.

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2015-11-17

Benefits of interface callbacks instead of class messages

If you compare with existing client/server SOA solutions (in Delphi, Java, C# or even in Go or other frameworks), mORMot's interface-based callback mechanism sounds pretty unique and easy to work with.

Most Events Oriented solutions do use a set of dedicated messages to propagate the events, with a centralized Message Bus (like MSMQ or JMS), or a P2P/decentralized approach (see e.g. ZeroMQ or NanoMsg). In practice, you are expected to define one class per message, the class fields being the message values. You would define e.g. one class to notify a successful process, and another class to notify an error. SOA services would eventually tend to be defined by a huge number of individual classes, with the temptation of re-using existing classes in several contexts.

Our interface-based approach allows to gather all events:

  • In a single interface type per notification, i.e. probably per service operation;
  • With one method per event;
  • Using method parameters defining the event values.

Since asynchronous notifications are needed most of the time, method parameters would be one-way, i.e. defined only as const - in such case, an evolved algorithm would transparently gather those outgoing messages, to enhance scalability when processing such asynchronous events. Blocking request may also be defined as var/out, as we will see below, inWorkflow adaptation.

Behind the scene, the framework would still transmit raw messages over IP sockets (currently over a WebSockets connection), like other systems, but events notification would benefit from using interfaces, on both server and client sides.
We will now see how...

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2015-09-16

Feedback from the Wild

We just noticed a nice feedback from a mORMot user. Vojko Cendak commented the well-known DataSnap analysis based on Speed & Stability tests blog article written by Roberto some months years (!) ago. It is not meant to be the final word, perhaps there was some tuning possible for RTC (which is  […]

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2015-09-14

Performance issue in NextGen ARC model - much better now

Back in 2013, I found out an implementation weakness in the implementation of ARC weak references in the RTL.
A giant lock was freezing all threads and cores, so would decrease a lot the performance abilities of any ARC application, especially in multi thread.

I just investigated that things are now better.

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2015-08-15

Breaking Change in mORMot WebSockets binary protocol

Among all its means of transmission, our mORMot framework features WebSockets, allowing bidirectional communications, and interface-based callbacks for real time notification of SOA events.
After several months of use in production, we identified some needed changes for this just emerged feature.

We committed today a breaking change of the data layout used for our proprietary WebSockets binary protocol.
From our tests, it would increase the performance and decrease the resource consumption, especially in case of high number of messages.

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2015-06-30

Faster String process using SSE 4.2 Text Processing Instructions STTNI

A lot of our code, and probably yours, is highly relying on text process. In our mORMot framework, most of its features use JSON text, encoded as UTF-8. Profiling shows that a lot of time is spent computing the end of a text buffer, or comparing text content. You may know that In its SSE4.2 feature  […]

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2015-06-21

Why FPC may be a better compiler than Delphi

Almost every time I'm debugging some core part of our framework, I like to see the generated asm, and trying to optimize the pascal code for better speed - when it is worth it, of course! I just made a nice observation, when comparing the assembler generated by Delphi to FPC's output. Imagine you  […]

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2015-05-18

CQRS Persistence Service of any DDD object with mORMot

We introduced DDD concepts some time ago, in a series of articles in this blog. At that time, we proposed a simple way of using mORMot types to implement DDD in your applications. But all Domain Entitities being tied to the framework TSQLRecord class did appear as a limitation, breaking the  […]

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2015-05-08

I do not like people shoot in my foot, do you?

There was some discussion about the new TStringHelper feature introduced in latest versions of Delphi.
I was told to be some kind of archaic guy, not able to see the benefit of this.
Reducing opinions to a conservative/progressive approach - another famous 10 kinds of coders - is very reductive.

Of course, this was IMHO unfair and my point was that I have the feeling that some decisions about the Delphi language and RTL are inadequate.
Some changes are welcome. I enjoy the introduction of generics - even if it is was painful, and even buggy (do not use TList<T> with managed record types in XE8!).
But some upcoming changes about the string policy - breaking everything just because we want to align with mainstream C# or Java habits - are just non sense to me.
I really think that Embarcadero deciders like to shoot their own foot.
Or - certainly worse - our own feet!

I will post here some part of the discussion...
So that we may be able to share our ideas.

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2015-02-21

SynCrypto: SSE4 x64 optimized asm for SHA-256

We have just included some optimized x64 assembler to our Open Source SynCrypto.pas unit so that SHA-256 hashing will perform at best speed.
It is an adaptation from tuned Intel's assembly macros, which makes use of the SSE4 instruction set, if available.

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2015-02-16

Benchmarking JsonDataObjects JSON parser

There is a new player in town.
Since it has been written by Andreas Hausladen, the maintainer of the great Delphi IDE fix packs, this new JSON library is very promising.

And in fact, it is fast, and sounds pretty great!
Here are some numbers, compared with SuperObject, standard DBXJson, dwsJSON, QDAC and mORMot.
Please refer to previous benchmark articles about those libraries. We will now focus on JsonDataObjects.

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2015-02-01

Benchmarking QDAC3 JSON parser

Do you know QDAC3 ?
This is an open source project, from China (with Chinese comments and exception errors messages, but the methods and variables are in English).
It is cross-platform, and told to be very fast about JSON process.

You can download this Open Source project code from http://sourceforge.net/projects/qdac3
And their blog - in Chinese - is at http://blog.qdac.cc/

So I included QDAC3 in our "25 - JSON performance" sample.
Numbers are talking, now.

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2015-01-15

AES-NI enabled for SynCrypto

Today, we committed a new patch to enable AES-NI hardware acceleration to our SynCrypto.pas unit. Intel® AES-NI is a new encryption instruction set that improves on the Advanced Encryption Standard (AES) algorithm and accelerates the encryption of data on newer processors. Of course, all this is  […]

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