Notes from SNIA’s Storage Developers Conference (SDC) 2010 and CIFS/SMB/SMB2 Plugfest
If you’re following me on Twitter, you probably noticed I am attending SNIA’s Software Developer’s Conference 2010 (SDC 2010) and the CIFS/SMB/SMB2 PlugFest this week.
The agenda for the event is published at https://www.snia.org/events/storage-developer2010/agenda2010.
Here are some random notes from the event, some of them taken from a few earlier tweets (some sessions are just mentioned, others have a few notes).
I’ll keep updating today and tomorrow.
PlugFest
- 25 companies attending the PlugFest
- The place was busy starting on Sunday, 09/19
- Windows Storage Server 2008 R2 “Birds of a Feather” session today at 7:30 PM, after the PlugFest Open House
- File Server Capacity Tool (FSCT) “Birds of a Feather” session today at 8:30 PM
Session: "The Long and Winding Road to SMB/CIFS specs" by Christopher Hertel and Jose Rivera (both from ubiqx)
- Christopher on CIFS: "CIFS is dead. Actually, CIFS is undead. Also, CIFS is documented."
- See [MS-CIFS] at https://msdn.microsoft.com/en-us/library/ee442092(PROT.10).aspx
- Christopher on SMB: "SMB=Server Message Block, Super Mario Brothers or Small and Medium Business" :-)
- See [MS-SMB] at https://msdn.microsoft.com/en-us/library/cc246231(PROT.13).aspx
- Christopher: "The old SMB/CIFS (pre-SMB2) is like the Winchester House, full of strange stairs, rooms and windows"
- Christopher on SMB2: "If you are a CIFS/SMB implementer and you are not working on SMB2, you are behind and you need to run to catch up."
- See [MS-SMB2] at https://msdn.microsoft.com/en-us/library/cc246482(PROT.13).aspx
- Christopher: "BranchCache is also documented and it further enhances WAN performance."
- Jose: "One good way to get started is the Implementing CIFS book. It's available online." https://ubiqx.org/cifs/Book.html
- Jose: "Free test suites: FSCT from Microsoft and smbtorture from Samba Team."
- Jose: "Unix Extensions for SMB2" https://www.unixsmb2.org/
Session: "MS-FSA: Describing wire visible behavior of MS File Systems" by Neal Christiansen, Microsoft
- [MS-FSA] documents algorithms that would otherwise have to be described in many other documents like CIFS, SMB, SMB2
- Available for download from https://msdn.microsoft.com/en-us/library/ff469524(PROT.10).aspx
- [MS-FSSC] (File System Control Codes) is an important support document for MS-FSA and other documents
- Available for download from https://msdn.microsoft.com/en-us/library/cc231987(PROT.13).aspx
- Going over a few of the algoriths described in [MS-FSA]
- Name tunneling: preserves attributes of the file in certain situations (from 8.3 name transition)
- Alternate Data Stream: Some interesting behaviors. For instance, by default, an empty primary DS is created
- Byte range locks. Interesting concept of zero length ranges. FSBO also has some more info on those
- USN journal or change journal. Describes the location points where the journal is updated
- Directory change notification. You can see the many trigger points, what flags are set
- Oplocks. How they are granted and how the different types interact. FSBO also has some nice tables on this
- Deleting files. Interesting details on delete-on-close and delete-pending states
- Valid Data Length (VDL). Allows setting file size without writing zeroes to newly allocated space
- Object GUID. File can be opened by ObjectID. Requirements for setting, retrieving
- Extended Attributes (EA). Name value/pairs to storage metadata associated with a file
- Reparse Points: An open can be redirected. Used by symbolic links. Mutually exclusive with EAs
- Symbolic Links and Mount Points. Implemented as reparse points
Session: “Challenges of 10 Gb iSCSI/FCOE Array Certification” by Mahmoud Jibbe, LSI
Session: “Comparison btw Samba 3 and Likewise Lwiod SMB FileServers” by Steven Danneman, Isilon
Session: “Status of Clustered CIFS Using Samba” by Volker Lendecke, Samba Team / SerNet
Session: “Implementing SMB2 within Samba” by Jeremy Allison, Google
Session: “SMB2 Meeting Linux” by Steve French, IBM
Session: Windows Storage Server 2008 R2 BoF session
- Covered the main differences between Windows Server 2008 R2 and Windows Storage Server 2008 R2
- Microsoft iSCSI Software Target 3.3
- Single Instance Storage (SIS)
- Browser-based Remote Management using RDP
- OOBE (Out-of-the-box Experience), including two-node cluster OOBE
- Highlights of the main improvements in the Storage Server Components
- For a recent webcast on WSS 2008 R2, check on https://www.msteched.com/2010/NorthAmerica/WSV323
File Server Capacity Tool (FSCT) BoF session today at 8:30 PM
- Overview of the tool itself, how it works, how to set it up
- Check https://blogs.technet.com/b/josebda/archive/2009/09/16/file-server-capacity-tool-fsct-1-0-available-for-download.aspx
- Also reviewed FSCT sample results from Scott’s presentation at https://ecn.channel9.msdn.com/o9/te/NorthAmerica/2010/pptx/WSV323.pptx
Session: Welcome Remarks by Wayne Adams (SNIA Board Chairman) and Mark Carlson (SDC Committee Chairman)
- SNIA CloudBurst Summit will be broadcast live on Thursday. https://www.snia.org/cloud/Cloudburst/
- SNIA also growing in Brazil. If you speak Portuguese, check https://www.snia.com.br/
Session: Clouds, Convergence and Consolidation by Henry Baltazar, The 451 Group. https://www.the451group.com/
- Where is the innovation? Cloud Storage Service, Hybrid Cloud Storage (on premises cloud gateway appliance)
- Hybrid Cloud Storage Examples: Bottomless NAS Gateway, Disaster Recovery Appliance, Primary Storage Replacement
- Convergence of Storage/Server/Network into super silos.
- FCoE right now only in limited use cases: Server to SAN connectivity "top-of-rack", Storage target conectivity.
- Solid State Storage - the driver is to close the Storage Performance "gap". Spinning drives not improving fast enough.
- SSD: Is MLC the key? Overcoming write endurance limitations. 3x more affordable than SLC. Enterprise ready?
- Where to deploy SSD? Server (PCI-E cards), Storage (embedded in the array), Network (bump in the wire cache)
- Storage vendors are now using more powerful CPUs and running apps on the storage systems themselves
Session: Long Term Information Retention by Sam Fineberg, HP
- If we want to keep data for 50 or 100 years we are talking going beyond the life span of any storage technology
- Disaster, human error, attacks, economic/organizational faults, media/hardware/software/format obsolescence, losing context
- A good archive is always in motion. You can't stuck a tape in a vault and expect to read it in 50 years.
- What's important in a book? The words in it, the paper it's made of, the political context of when it was written?
- Storage formats. We can't predice the future. Key properties: Self contained, Self describing, Extensible.
- SNIA's SIRF (Self Contained Information Retention Format) and Preservations Objects. https://www.snia.org/events/storage-developer2009/presentations/tuesday/Fineberg-Cohen_LTRFormat.pdf
Session: Solid State Storage Panel Discussion: “Is Solid State Storage Ready for Primetime?”
Tom Coughlin (Moderator), Coughlin Associates; Marty Czekalski, Seagate; Jim Handy, Objective Analysis; Dr. Easen Ho, Calypso Systems, Inc; Esther Spangler, Smart Modular
- Tom Coughlin
- Looking at cost trends for flash memory and hard disk drives.
- Historic symbiotic relationship between flash and HDDs in consumer devices
- Symbiotic combination of Flash memory and HDDs in computers
- Calypso SSD Blind Survey 2010. Comparing SLC, MLC and HDD. https://calypsotesters.com/testing.html
- Flash Use: consumer applications, USB sticks. LA new cache layer? Use some flash or more DRAM for caching?
- Hetzler’s Chasm Cache Analysis (S. Hetzler, IBM). Two chasms: DRAM-SATA, SATA-Tape. https://www.caiss.org/docs/DinnerSeminar/TheStorageChasm20090205.pdf
- Dual drive (tiering on your computer – Marvell, Hitachi, Toshiba) and hyrid HDD (Seagate) approaches
- Dual drive: How much SDD do you need to storage your applications? 40GB is enough. User data goes to a HDD.
- Hybrid drives, totally transparent to the OS. Putting items you access more often on the SSD. Boot gets faster multiple reboots.
- Options: Flash Cache Module, Solid State Drive, Solid State Hybrid Drive.
- Hytachi-LG HyDrive – Optical disk with flash memory drive for dual storage laptops. https://www.engadget.com/2010/05/31/hitachi-lg-goes-official-with-hydrive-ssd-equipped-optical-driv/
- HDD: Latency issues. Uses DRAM or flash memory for cache? Intel likes flash and hard drives. Seagate likes hybrid drives.
- Jim Handy
- The DRAM/HDD Speed Gap chart: Tape, HDD, DRAM, L3, L2, L1 – Price per GB vs. Bandwidth in MBps (logarithmic scale)
- Options: Keep more data in DRAM (more RAM, more servers) or use accelerated HDDs to fill the gap ($300, short-stroked)
- In 2004 NAND shot past DRAM’s price per GB. 1/12th the cost now and growing. NAND is slower/cheaper than DRAM and faster than a HDD.
- Yesterday, Violin announced a 40TB SSD. “Put the whole database into flash!” $16 per GB and $3 per IOPS. https://www.violin-memory.com/news/press-releases/violin-memory-quadruples-data-center-density-with-40tb-capacity-flash-memory-array/
- Automatic Tier Management: autonomous (controllers) or operating system support. Many more to come!
- Performance muse be understood. Performance is not always intuitive
- PC: 1 HDD, no hierarchy, speed is nice to have. Data Center: thousands of HDD, storage hierarchy, speed is money
- PC architectures will follow the data center example. Main storage cached by flash. It’s going to happen, it’s just a matter of when.
- Panel discussion
Session: Interoperability Tools for CIFS/SMB/SMB2 by Paul Long and Simon Sun, Microsoft
- [MS-FSSO] is great place for an overview of file-related protocols. Great place to start.
- You can also use the MSDN support forums
- Network Monitor
- Parsers updated monthly. You can modify/add parsers.
- Conversation tree is nice.
- Rich filtering and colorization of frames.
- Frame annotations
- Network monitor. Four sources of captures
- GUI Capture from NDIS capture driver
- NMcap / command line tool to enable/disable capture from a batch file
- Pcap file format – import captures from other tools like tcpdump, wireshark
- Event Tracing for Windows. Using netsh trace, logman. Can capture during reboot.
- Netmon API. Can be used for capture or parsing (what is the SMB command in this frame?)
- Experts / Top users / Top protocols / SSL decrypt / ...
- Interoperability Test Suite
- Captures to help you understand with annotations, reference to doc pointer - https://sysdoccap.codeplex.com
- Look for the file sharing system docs
- Why reviewing packets against the protocol specification if netmon can do the first pass for you?
- Parsers error will point to frames with issues. Also look at SMBerrors
- There cloud be errors in the parsers, but most of the time…
- Can also help you locate the protocol document doc based on a trace. Option to Go to data type definition
- Spec explorer: Use a model to create tests: start with spec, create implementation from spec, write tests to check conformance
- Model used to generate tests – provide input and check expected output
- Hand create model, not test: Spec explorer handles model/input/output
- Interop test suite:
- Validate protocol doc aginst windows implementation. Verify conformance/accuracy/usability of protocol doc
- Interop test: see https://www.microsoft.com/openspecifications/appliedinterop
- Netmon vs wireshark
- Netmon: parsers are very complete, focus on applications, can capture multiple NICs
- Wireshark: more feature rich in general, more focused on lower layers
- Interop test suite: Intent to release source code in a VHD in the future. No specific timeline yet. Working on it.
Session: SMB Traffic Analyzer - Monitor the Data Flow of Samba Servers, Holger Hetterich, Novell
Session: Evaluating SMB2 Performance for Home Directory Workloads by David Kruse and Dan Lovinger, Microsoft
- Options: Performance counters, network captures, windows perform ance analysis tool
- Answering deeper questions. Am I storage, network or CPU bound? Am I seeing a high level of lock contention?
- Event-based model – Log Request, Gather execution info, Log Response + Execution Info
- Execution slicing
- Data mining
- Analyzing an FSCT run to look at local handle count across time, seconds per operation for each type of request
- Evaluating the HomeFolders workload of the File Server Capacity Tool (FSCT)
- Describing FSCT. Overview of the tool, history of its development, details about how it simulates a workload.
- Homefolders: User follows a frequency distribution of scenarios, with ~1 scenario every 11 seconds.
- Capacity metric: How many users the server can satisfy without overload (delayed scenarios)
- Initial Physical Model: Client (SMB RDR), SMB Server, Storage Stack, Disk Subsystem. Track what happens at each level.
- Model with compounding: 1 packet with multiple operations. Latency equation taken that into consideration
- Measuring HomeFolders: SMB 2.1 total wire operations per FSCT scenario.
- SMB Investigation: Modeling of Directory Cache Improvements vs. Directory Leases. Second one seems much better.
- Latency Estimates;
- Use the model to extrapolate to real hardware.
- FSCT used to load low-end reference server, captured counters at near overload.
- High Variance. Some large tails on the CREATE operation
- Scaled scenarios. Extrapolate from LAN to WAN by adding 2-20ms client-server network latency
- These are purely investigations, but shows how a performance model like this can be useful.
- Consider performance counters and events in your design process
- New protocols are opportunities to revisit your performance infrastructure
- More data = More insight = Better designs, earlier
- Extrapolation models can be an interesting input to the design process
Session: Scaling Likewise-CIFS Beyond 50k Concurrent Connections on a Single Node, by Gerald Carter, Likewise Software
- Likewise as defined by Gerald: “Interoperability platform for non-Microsoft clients and servers in Microsoft OS dominated networks.” https://www.likewiseopen.org
- Gerald quotes on performance:
- “No one cares about performance until it’s not there.”
- “Workloads, much like people, are rarely objective.”
If you are registered for the event, get the decks from https://www.snia.org/events/storage-developer2010/presentation
For everyone else, the decks are typically made available to the public a few months after the event. I’ll make sure to blog about it when it happens.