Showing posts with label network fabric. Show all posts
Showing posts with label network fabric. Show all posts

Tuesday, August 23, 2016

[Links of the day] 23/08/2016 : Adapting In memory database architecture for Storage class memory and Datacenter network congestion management

  • The implication of Storage Class Memory for In memory database architecture : 
    • SOFORT : The authors propose to modify traditional In memory database architecture in order to optimise its operation for upcoming storage class memory hardware. The idea is quite simple, get rid of the log mechanism and persist all data to NVM except for the index which needs to be maintained in RAM for performance requirement. SCM allow to drastically eliminate a lot of boiler plate architecture functionality by delivering fast byte addressable persistent storage. However, now the developers needs to be aware of the transnational model imposed by this new class of persistent memories. [Slides]
    • Instant Recovery for Main-Memory Databases : This paper build on top of SOFORT and looks at leveraging NVDIMM or SCM for speeding up crash recovery features. The idea is not only speed up the normal operation but also eliminate the recovery cost in case of application crash [Slides]
    • Note that both these paper have an author working for SAP, so my guess that we will start to see new dedicated feature in SAP Hana for supporting SCM.
  • Flowtune : It seems that we are going to see slowly a return of the ATM model in data-center for networking fabric. In this paper the author propose to combine a form of MPLS system with a centralized allocator for resources management and congestion avoidance.  Basically the system identify connection ( called flowlet )  establishment  and end . Using the existing and past information it derive an optimal path and resources allocation minimizing interference and congestion over the lifetime of the flowlet. Looks like SDN is finally enabling a simplified and more robust ATM model within and probably across data-centers. 

Wednesday, June 29, 2016

[Links of the day] 29/06/2016 : Behavioral Economics , Tofu and RapidIO interconnect

  • Behavioral Economics Guide 2016 : Document looking at behavioral economics, the key takeaway that can be applied almost anywhere: when facing a problem or situation where all outcomes and probabilities are known and where the past determine the future (or looks like it), then you should leverage fine-tuned solutions such as complex optimization techniques. However if you have ( a significant ) uncertainty, then using robust solutions, including simple heuristics deliver better results. Sadly, the human nature tend to go for complexe solution in uncertain situation.. 
  • Tofu 2 : system interconnect (25Gbps) designed for the successor model of the FUJITSU Supercomputer PRIME HPC FX10. [slides]
  • Low Latency Analytics and Edge Connected Vehicles with RapidIO Interconnect : Interesting to see that rapidio interconnect is still alive and kicking. Looks like they are positioning as a full network stack solution ranging from cpu - cpu to box - box and with emphasis on IoT / analytic 

Tuesday, June 28, 2016

[Links of the day] 28/06/2016 : Heterogeneous Data-centers (FPGA - GPU) and User-mode Ethernet verbs

  • Heterogeneous datacenters : Datacenter slowly evolve and we start to see the emergence of specialized dedicate hardware to squeeze the maximum efficiency per watts consumed. As general CPU start to hit their limit, user turn , like the HPC community, to FPGA or GPU to break away of the current power wall. 
  • A quantitative analysis on microarchitectures of modern CPU-FPGA platforms : Well if you want to venture in the heterogeneous datacenter you better read this paper on the different platform available out there. 
  • User Mode Ethernet Verbs : Probably the only serious contender to Intel DPDK, User mode verbs expose Verbs API allowing both user-mode applications/ULPs direct access to offload capabilities in the form of Raw Ethernet QPs. Basically you can send receive raw ETH packet using RDMA verbs API and leverage offload engine to accelerate the operations [video]

Thursday, May 12, 2016

[Links of the day] 12/05/2016: Lustre + Omnipath in Bridges Supercomputer & Storage Media Evolution

  • Lustre + Omnipath : HPC filesystem of choice meet Intel Omnipath fabric. Intel was poised to release such crossover as it continue to push in the HPC domain and rack infrastructure domination . Remember that  Intel acquired Whamcloud (Lustre) a while back.
  • Storage Media Overview: Historic Perspectives of storage solution. Interesting snippet of information all storage media revenue decreased from 2014 to 2015 except for NAND. However, NAND revenue increased by 30% in 2014 but only 3% in 2015. Hinting a plateau of the tech and entering a commoditization phase with lower margin. [Video]
  • Bridges :supercomputer being built at the Pittsburgh Supercomputing Center (PSC), they have a really cool Virtual Tour .


Monday, May 02, 2016

[Links of the day] 02/05/2016 : All about storage @ Intel IDF 16 + no more secret


Friday, March 18, 2016

[Links of the day] 18/03/2016: RethinkDB FS and NSDI16 - Load balancer, reconfigurable fabric

  • Google Load Balancer : Google use a N+1 model for its load balancer vs the classical Active/passive model. Really nice low level network load balancing solution. 
  • XFabric : Reconfigurable In-Rack Network for Rack-Scale Computers
  • Regrid : a method of storing large files inside a RethinkDB database. Each file is stored as a series of binary chunks inside RethinkDB
  • NSDI16 : this year harvest of Usenix networking papers.

Tuesday, March 08, 2016

[Links of the day] 08/03/2016 : Deeplearning google tech talk, NVMW 2016 workshop







Tuesday, March 01, 2016

[Links of the day] 01/03/2016 : DSSD , Datacenter design [book] and latent faults [paper]

  • DSSD : EMC released into the wild DSSD product (acquired last year). Quite a beast: all flash, 10 M IOPs, 100μs latency, 100GB/s BW, 144TB/5U. It use a PCIe fabric to connect the storage to the compute nodes, however I expect them to move soon to infiniband / omnipath fabric based on the talk they recently made.
  • Datacenter Design and Management: book that surveys datacenter research from a computer architect's perspective, addressing challenges in applications, design, management, server simulation, and system simulation.
  • Unsupervised Latent Faults Detection in Data Centers : talk and paper that look at automatically enable early detection and handling of performance problems, or latent faults. These faults "fly under the radar" of existing detection systems because they are not acute enough, or were not anticipated by maintenance engineers.
Rolex Deep Sea Sea Dweller (DSSD)


Tuesday, January 26, 2016

[Links of the day] 26/01/2015: All about SNIA NVM summit 2016

NVM Summit : January 20th 2016 SNIA summit on non volatile memory, here are some of the interesting slides deck:
  • Solid State storage Market : nothing really new, we have to wait until 3dxpoint reach the market to shake things up. Hopefully it will help accelerate the drop of $ per GB even if the trend shown below seems to stall over the next few years. 
  • Going Remote at low latency : a look into what type of change would be necessary to improve the RDMA API in order to facilitate directe NVM access, bypassing the NVMe over fabric altogether.
  • Persistent Memory over Fabric : Well mellanox is obviously edging its bet here, but lets see how the NVMf stack evolve.

Friday, January 08, 2016

Links of the day 08/01/2016: Cloud storage performance, Cray XC network , Compute in Cloud + on premise storage

  • Cray XC : distributed memory system for the cray system. It allow a global access via the fabric to all the memory within the system. To do so it leverage the ARIES router system to create a high speed interconnect. Bandwidth , latency and routing capabilities are quite impressive and beat classical Infiniband offer out there.
  • AWS S3 vs Google Cloud vs Azure: Cloud Storage Performance , lowest latency are delivered by Amazon and Azure while Google beat them on throughput, for both uploads and downloads.
  • Compute in cloud and on premise storage : Not sure of what to think about it, there is so many constraint and problems with this approach. I would say that it might look like a solution looking for a problem. I can't see any clear use case that would justify such approach due to the technical constraint in term of bandwidth, latency, timeline, etc..



Tuesday, December 01, 2015

Links of the day 01/12/2015 : VISC, HP "machine" network fabric, Emu real time analytics server

  • VISC : Researcher are trying to improve the security, reliability, and performance implications of shipping all software in virtual instruction set form. They use the LLVM virtual instruction set as the shipping representation of code to enable install-time and run-time compilation of all such software. Probably a lot of potential there if coupled with uni-kernel tech. 
  • Communications fabric for The Machine : HP session presenting their own fabric, competing with Intel Omnipath, PCIe and others already out there. The risk is that it might be too specialized for an industry wide adoption unless they start to aggressively "give it way" the IBM openpower way. 
  • Emu : New type of server where the processing is moved to the data with a distributed shared memory model and high speed fabric. Seems like a revival of the connection machine for real time analytic solution. What is interesting is that they use a RapidIO fabric.

Thursday, November 19, 2015

Links of the day 19/11/2015: #ARM rack scale infrastructure fabric, Canonical ByoHW #Cloud software and Next Gen #Bigdata Storage

  • X-Tend : Applied micro get into the rack scale computing market with its ARM server and now the fabric to enable and support dis-aggregation of the resources. What is interesting there is since the ARM processor are more nimble in a certain sens it might make them more suitable for this paradigm than the big Intel processor. And if you throw into the mix hybrid and heterogeneous processors might end up having a better fit as you can more easily tailor the resource to your need as well as the power consumption coupled with it.
  • Autopilot : canonical private ByoHW cloud solution (more about that in another post).
  • Pyro: A Spatial-Temporal Big-Data Storage System for high resolution geometry queries and dynamic hotspots.


Wednesday, September 16, 2015

The upcoming Storage API battle

There is an interesting trend within the storage ecosystem. We are witnessing a polarization of the offer. On one side, we are seeing the rise of high performance rack scale solution(DSSD, NVMe over fabric solution, etc..) . And on the other side we have the object storage solution which are more datacenter scale. While both leverage heavily non volatile memory they play a different different role within the ecosystem.

The rack scale storage target “very” high performance solution, delivering very low latency high bandwidth access time. Often in the 100 of usec or less. However often these solution come at a higher financial cost due to more expensive hardware (custom NVM), network fabric (IB+NVMe, PCIe + NVMe, Omnipath +NVMe, Pure PCIe, etc..) and significant power consumption (>2000W/5U for DSSD). Finally, these offer access via a specialized API that needs to be either accessed natively or adapted to other more standard one.
On the other side we have the object storage solution. Users access object storage through applications that will typically use a REST API. This makes object storage ideal for all online, Cloud environments. Moreover they tend to be a lot more cost efficient especially with the rise of Ethernet connected drives (up to 50% less TCO).
Stuck in the middle is the classic Filer / POSIX compliant solution that seems to slowly dwindle away. To a certain extent the rack scale solution should have a bright future in the niche (but still significant) market for enterprise that still consider that their application requires custom for what they think is a custom problem. On the other side the object storage is gaining momentum by riding the unstoppable cloud tide.



While, both technology can and should co-evolve, they both suffer from software limitation and to a certain extend hardware one as bandwidth and latency get dangerously close to what cpu are capable to handle. This requires a drastic shift on how applications are developed if user want to actually get any benefit from these solution. However, few company are willing to risk specializing their code using an API that can become obsolete when the next generation of storage solution pops up.
Storage startup/company out there start to discover that  API is playing a significant role success of their product and performance while still important will lose of its importance. It will either make rewriting applications to access your storage infinitely easier task or transform it into a painful experience by forcing to go through hoops and/or adaptation layers with the performance cost associated. 
The fight for the next generation storage API only started. There is and will be more push toward standardization which will be fueled by the customer tiredness with every revolving siloed point solution. People who use object storage one want it to behave more like POSIX storage, but they also want to keep the storage costs at an object level and improve the performance. On the other hand people using rack scale storage want to retain the performance but increase its simplicity and also want the price to come down. It is going to be extremely hard to deliver both but hopefully we might finally see a rationalization of the storage market as having an object storage system that allows byte range access is very appealing. 

Friday, August 28, 2015

Links of the day 28/08/2015 : libfabric, IO visor and demoscene

  • IO visor : it seems that the effort from Plumgrid around eBPF are picking up speed and an official linux foundation project is been setup. However one must wonder how such solution will compete against the pure user space solution relying on DPDK and consort? You can find a more in depth slide deck of the concept [here].
  • Libfabric : Intel is announcing in grand pomp the "Open source" library supporting its Omni path fabric. However it is not other that the fantastic Lib fabric. This library offer a set of next-generation, community-driven, ultra-low latency networking APIs. The APIs are not tied to any particular networking hardware model, it support Infiniband / Iwarp, usNic from Cisco, OPA from intel What is interesting is that it goes one step further than the RDMA library while maintaining a good balance between low level tuning and high level program-ability. While the learning curve might be a little bit more steep compared to Accelio from Mellanox it delivers ( I think ) greater advantage and flexibility.
  • Winning 1kb intro : released at Assembly 2015, prepare to be amazed


Wednesday, August 12, 2015

Links of the day 12/08/2015 : #Google #Datacenter network, #Intel Omni-path Fabric and hardware x86 cpu security flaw

  • Memory sink hole : when x86 processors ancient (unused by now) feature bites back : it allows to move the memory window of the APIC registers to an arbitrary address. By moving this window, it is possible to circumvent built-in hardware security checks and access the highly privileged System Management Mode (Ring -2) from Ring 0 Code.
  • Google Datacenter Network : very good overview of the ONS keynote [video
  • Intel Omni-Path Architecture Webinar Series: very good overview of intel next gen fabric. Its really interesting how they place it directly in competition with infiniband. It seems that the PCI fabric fell completely off the radar and might stay stuck to niche solution.

Tuesday, April 21, 2015

Links of the day 21 - 04 - 2015

Today's links 21/04/2015: #NVM architecture, #HPC storage fabric, Cluster sqlite, Just in time #Unikernel Quic protocol
  • Architecture-level Designs using Emerging Non-volatile Memories : describe architecture techniques necessary for building efficient and reliable systems with NVMs.
  • Jitsu : Just-In-Time Summoning of Unikernels using a Xen toolstack that satisfies the demands of secure multi-tenant isolation on resource-constrained embedded ARM devices. 
  • Fortissimo : A3CUBE Fortissimo Foundation, computing/storage converged solution and data engine, provides a very fast and scalable platform for storing and retrieving data items with 100s of gigabytes/s of throughput and Mega IOPS. But as always hte catch is that it requires a proprietary fabric to do so which limits its adoption [Architecture] [Benchmark
  • rqlite : Cluster of sqlite using Raft protocol, really cool implementation. I wonder if it could be used as a for of fast ACID compliant distributed cache for SQL DB [github]
  • quic : Google pushing for their udp based protocol as IETF standard

Friday, February 20, 2015

Links of the day 20 - 02 - 2015

Links of the day 20/02/2015:Probabilistic counters, Rack PCIe Fabric, Complex Networks robustness, High performance Network protocol
  • Characterizing Storage Workloads with Counter Stacks : Really great approach to use hyperloglog algorithm to characterize workloads. It allow the identification of working set sizes without the large memory overhead . The key advantage is it allow the generation of accurate MRC for large workload without the tremendous overhead which then can be used to tweak the cache size and for online placement decision.
  • Rack Level PCIe fabric : looks like the competition is heating up for the next gen rack level fabric. There is some really nice feature in there, advanced topology ( torus, 3D fat tree), support for native tcp/ip , rdma and native. And last but not least sharing of I/O by the assignment of the VFs of SR-IOV . Not to forget that most ops are sub micro seconds. Its nice to see the rack level fabric competition heating up.
  • Improving the Robustness of Complex Networks with Preserving Community Structure : 3-step strategy to improve the robustness of a network, while retaining its community structure, and also its degree distribution.
  • Trickles : Stateless High Performance Networking that relies on Transport continuations information within the packet for congestion control algorithm , effectively removing the state maintenance on both side. Creating a stateless protocol at the cost of periodical update signal.

Wednesday, February 11, 2015

Links of the day 11 - 02 - 2015

Today's links 11/02/2015: Test and optimization articles, scaling product team, PCIe vs Eth , Distributed Sys fallacies
  • 100 Must-Read Articles on Testing and Optimization : data driven, big data, a/b testing etc.. The best articles from 2014
  • Scaling a product team : lesson learned from Intercom on how they scaled a product building team, and the nitty gritty involved in getting valuable product out the door as fast as possible.
  • Eight Fallacies of Distributed Computing : very good tech talk with real life encounter of the fallacies.
  • PCIe vs Ethernet : with the rise of Intel’s silicon photonics (SiPh) optical PCIe (OPCIe) and other PCIe fabric, is it time to fragment your datacenter and use fast PCIe rack fabric and Eth for cross rack one. To be honest time will tell as you already know the best technology doesn't always win.

Friday, November 28, 2014

Links of the day 28 - 11 - 2014

Today's links 28/11/2014: #Cloud Ressource Marketplace, Stream / Even processing, #bigdata benchmark, Facebook Fabric, Software Defined #IaaS

  • Deutsche Börse Cloud Exchange : market place for trading Compute, Memory and Storage. Interesting but the market place size looks really tiny, the available resources advertised could be added in just one day of daily operation of AWS. 
  • Flafka : Apache Flume Meets Apache Kafka for Event Processing
  • Terraform : common configuration to launch infrastructure — from physical and virtual servers to email
  • Facebook fabric: in depth analysis of Facebook data-center network fabric and its implication. 
  • Big Bench : Industry standard Bigdata analytic.


Monday, November 17, 2014

Links of the day 17 - 04 - 2014

Today's links 17/04/2014: distributed transaction, data center fabric, SSD friendly alternative to bloom filter.

  • Granola: Paper Summary: Granola, Low overhead distributed transaction coordination
  • Consistency and coordination : you do not always need coordination to be consistent while retaining ACID property [paper]
  • Quotient filter : SSD optimized alternative to bloom filter.
  • Facebook datacenter fabric : facebook we broke the network up into small identical units – server pods – and created uniform high-performance connectivity between all pods in the data center in order to maintain performance, scalability and reliability.