CASPUR Slab 0603

CASPUR / GARR / CERN / CNAF / CSP New results from CASPUR Storage Lab : 

CASPUR / GARR / CERN / CNAF / CSP New results from CASPUR Storage Lab Andrei Maslennikov CASPUR Consortium June 2003

Slide2: 

Participated: CASPUR : M.Goretti, A.Maslennikov(*), M.Mililotti, G.Palumbo ACAL FCS (UK) : N. Houghton GARR : M.Carboni CERN : M.Gug, G.Lee, R.Többicke, A.Van Praag CISCO : L.Pomelli CNAF : P.P.Ricci, S.Zani CSP Turin : R.Boraso Nishan (UK) : S.Macfall (*) Project Coordinator

Slide3: 

Sponsors: E4 Computer : Loaned 6 SuperMicro servers (MBs and assembly) - excellent hardware quality and support – Italy Intel : Donated 12 x 2.8 GHz Xeon CPUs San Valley Systems : Loaned two SL1000 units - good remote CE support during tests ACAL FCS / Nishan : Loaned two 4300 units - active participation in tests, excellent support CISCO Systems : Loaned two MDS 9216 switches with FCIP modules - active participation in tests, excellent support

Contents: 

Contents Goals Components and test setup Measurements: - SAN over WAN - NAS protocols - IBM GPFS - Sistina GFS Final remarks Vendors’ contact info

Goals for these test series: 

Feasibility study for a SAN-based Distributed Staging System Comparison of the well-known NAS protocols on latest commodity hardware Evaluation of the new versions of IBM GPFS and Sistina GFS as a possible underlying technology for a scalable NFS server. Goals for these test series

Remote Staging: 

Feasibility study for a SAN-based Distributed Staging System - Most of the large centers keep the bulk of the data on tapes and use some kind of disk caching (staging, HSM, etc) to access these data. - Sharing datastores between several centers is frequently requested, and this means that some kind of mechanism that would allow to access the data stored on the remote tapes should be proposed. - Suppose now that your centre has implemented a tape<->disk migration system. And you have to extend your system to allow it to access the data dislocated on remote tape drives. Let us see how this can be achieved. Remote Staging

Remote Staging : 

Solution 1: To access a remote tape file, stage it on a remote disk, then copy it via network to the local disk. Local Site Remote Site Remote Staging Disk Tape Disk Disadvantages: - 2-step operation: more time is needed, harder to orchestrate - Wasted remote disk space

Remote Staging : 

Solution 2: Use a “tape server”: a process residing on a remote host that has access to the tape drive. The data are read remotely and then “piped” via network directly to the local disk. Local Site Remote Site Remote Staging Disadvantages: - remote machine is needed - architecture is quite complex

Remote Staging : 

Solution 3: Access the remote tape drive as a native device on SAN. Use it then as if it is a local unit attached to one of your local data movers. Local Site Remote Site Remote Staging Benefits: - Makes the staging software a lot simpler. Local field-tested solution applies. - Best performance guaranteed (provided the remote drive may be used locally at native speed) SAN

Remote Staging : 

“Verify whether FC tape drives may be used at native speeds over the WAN, using the SAN-over-WAN interconnection middleware” - In 2002, we had already tried to reach this goal. In particular, we used the CISCO 5420 iSCSI appliance to access an FC tape over the 400 km distance. We were able to write at the native speed of the drive, but the read performance was very poor. - This year, we were able to assemble a setup which implements a symmetric SAN interconnection and hence used it to repeat these tests. Remote Staging

NAS protocols: 

Benchmark the well-known NAS protocols on a modern commodity hardware. - These tests we do on a regular basis, as we wish to know what performance we may currently count on, and how the different protocols compare on the same hardware base. - Our test setup was visibly more powerful than that of the last year, so we were expecting to obtain better numbers. - We were comparing two remote copy protocols: RFIO and Atrans (cacheless AFS), and two protocols that provide the transparent file access: NFS and AFS. NAS protocols

Scalable NFS Server: 

Evaluate the new versions of IBM GPFS and Sistina GFS as a possible underlying technology for a scalable NFS server. - In 2002, we have already tried both GPFS and GFS. - GFS 5.0 has shown interesting performance figures, but we have observed several issues with it: unbalanced perfomance in case of multiple clients, exponential increase of load on the lock server with increasing number of clients. - GPFS 1.2 was showing a poor performance in case of concurrent writing on several storage nodes. - We used GFS 5.1.1 and GPFS 1.3.0-2 during this test session. Scalable NFS Server

Components: 

- High-end Linux units for both servers and clients 6x SuperMicro Superserver 7042M-6 and 2x HP Proliant DL380 with: 2 CPUs Pentium IV Xeon 2.8GHz SysKonnect 9843 Gigabit Ethernet NIC (fibre) Qlogic QLA2300 2Gbit Fibre Channel HBA Myrinet HBA - Disk systems 4x Infortrend IFT-6300 IDE-to-FC arrays: 12 x Maxtor DiamondMax Plus 9 200 GB IDE disks (7200 rpm) Dual Fibre Channel outlet at 2 Gbit Cache: 256 MB Components

Components -2: 

- Tape drives 4x LTO/FC (IBM Ultrium 3580) - Network 12-port NPI Keystone GE switch (fibre) 28-port Dell 5224 GE switches (fibre / copper) Myricom Myrinet 8-port switch Fast geographical link (Rome-Bologna, 400km), with guaranteed throughput of 1 Gbit. - SAN Brocade 2400, 2800 (1Gbit) and 3800 (2Gbit) switches SAN Valley Systems SL1000 IP-SAN Gateways Nishan IPS 4300 multiprotocol IP Storage Switches CISCO MDS 9216 switches with DS-X9308-SMIP module Components -2

Components -3: 

New devices We were loaned three new objects: from San Valley Systems, from Nishan Systems, and from CISCO Systems. All these units provide the SAN-over-IP interconnect function, and are suitable for wide-area SAN connectivity. Let me give some more detail of these units. Components -3

Slide16: 

San Valley Systems IP-SAN Gateway SL-700 / SL-1000 - 1 or 4 wirespeed Fibre Channel -to- Gigabit Ethernet channels - Uses UDP and hence delegates to the application the handling of a network outage - Easy in configuration - Allows for the fine-grained traffic shaping (step size 200 Kbit, 1Gb/s to 1Mb/s) and QoS - Connecting two SANs over IP with a pair of SL1000 units is in all aspects equivalent to the case when these two SANs are connected with a simple fibre cable - Approximate cost: 20 KUSD/unit (SL-700, 1 channel) 30 KUSD/unit (SL-1000, 4 channels) - Recommended number of units per site: 1

Slide17: 

Nishan IPS 3300/4300 multiprotocol IP Storage Switch - 2 or 4 wirespeed iFCP ports for SAN interconnection over IP - Uses TCP and is capable to seamlessly handle the network outages - Allows for traffic shaping at predefined bandwidth (8 steps,1Gbit- 10Mbit) and QoS - Impements an intelligent router function: allows to interconnect multiple fabrics from different vendors and makes them look as a single SAN - When interconnecting two or more separately managed SANs, maintains their independent administration - Approximate cost: 33 KUSD/unit (6 universal FC/GE ports + 2 iFCP ports - IPS 3300) 48 KUSD/unit (12 universal FC/GE ports + 4 iFCP ports - IPS 4300) - Recommended number of units per site: 2 (to provide redundant routing)

Slide18: 

CISCO IP Storage Services Module (DS-X9308-SMIP) - Provides integration of IP Storage Services into the Cisco MDS9000 FC switches (One MDS9216 switch incorporates 16 FC ports) - 8 Gigabit Ethernet IP Storage Interfaces: o Wire-rate FCIP on all ports simultaneously o Up to 24 simultaneous FCIP links per module - Industry standard FCIP protocol uses TCP/IP to provide reliable transport - VSAN and VLAN services increase stability and security of WAN-connected SAN elements - Pricing provided through reseller partners (IBM, HP and others) - Recommended number of units per site: 1

CASPUR Storage Lab: 

CASPUR Storage Lab HP DL380 Bologna IPS 4300 SL1000 HP DL380 Rome SM 7042M-6 SM 7042M-6 Myrinet IPS 4300 SL1000 1 Gbit WAN, 400km MDS 9216 MDS 9216

Series 1: accessing remote SAN devices: 

Series 1: accessing remote SAN devices Disks Tapes IPS 4300 SL1000 IPS 4300 SL1000 1 Gbit WAN, 400km HP DL380 Bologna HP DL380 Rome MDS 9216 MDS 9216

Series 1 - current results: 

- We were able to operate with tape drives at the drive native speed (R and W): 15 MB/sec in case of LTO and 25 MB/sec in case of another, faster, drive - In case of disk devices we have observed a small (5%) loss of performance on writes and a more visible (up to 12%) loss on reads, on all 3 units. The performance drop on reads increases with distance between the units: 6% at 1 m through 10-12% at 400 km. - Several powerful devices used simultaneously over the geographical link easily grab the whole available bandwidth of the GigE link between the two appliances (seen so far for Nishan and San Valley units only; CISCO will be tested in the close future). - in case of Nishan (TCP-based SAN interconnection) we have witnessed a successful job completion after an emulated 1-minute network outage. A similar test will also be performed for the CISCO unit. Distributed Staging based on a direct tape drive access is POSSIBLE ! Series 1 - current results

Series 2 – Comparison of NAS protocols: 

Series 2 – Comparison of NAS protocols Server SM 7042 Client SM 7042 Gigabit Ethernet RAID 50 R/W: circa 150 MB/sec Infortrend IFT6300 FC 2 Gbit Infortrend IFT6300

Series 2 - details: 

Some settings: - Kernels on server: 2.4.18-27 (RedHat 7.3, 8.0) - Kernel on client: 2.4.20-9 (RedHat 9) - AFS : cache was set up on ramdisk (400MB) - used ext2 filesystem on server Problems encountered: - Poor array performance on reads with kernel 2.4.20-9 Series 2 - details

Series 2 – more detail: 

Write tests: - Measured average time needed to transfer 20 x 1.9 GB from memory on the client to the disk of the file server and vice versa including the time needed to run “sync” command on both client and the server at the end of operation: 20 x {dd if=/dev/zero of=<filename on server> bs=1000k count=1900} T=Tdd + max(Tsyncclient, Tsyncserver) Read tests: - Measured average time needed to transfer 20 x 1.9 GB files from a disk on the server to the memory on the client (output directly to /dev/null ). Because of the large number of files in use and the file size comparable with available RAM on both client and server machines, caching effects were negligible. Series 2 – more detail

Series 2- current results (MB/sec) [SM 7042 - 2GB RAM on server and client]: 

Series 2- current results (MB/sec) [SM 7042 - 2GB RAM on server and client]

Series 3a – IBM GPFS: 

Series 3a – IBM GPFS 4 x IFT 6300 disk arrays SM 7042M-6 SM 7042M-6 SM 7042M-6 SM7042M-6 NFS

Series 3a - details: 

GPFS installation: - GPFS version 1.3.0-2 - Kernel 2.4.18-27.8.0smp - Myrinet as server interconnection network - All nodes see all disks (NSDs) What was measured: 1) Read and Write transfer rates (memory<->GPFS file system) for large files 2) Read and Write rates (memory on NFS client<->GPFS exported via NFS) Series 3a - details

Series 3a – GPFS native (MB/sec): 

Series 3a – GPFS native (MB/sec) R / W speed for a single disk array: 123 / 78

Series 3a – GPFS exported via NFS (MB/sec): 

Series 3a – GPFS exported via NFS (MB/sec) 1 node exporting 2 nodes exporting 3 nodes exporting

Series 3b – Sistina GFS: 

Series 3b – Sistina GFS 4 x IFT 6300 disk arrays SM 7042M-6 SM 7042M-6 SM 7042M-6 SM7042M-6 SM7042M-6 NFS Lock Server

Series 3b - details: 

GFS installation: - GFS version 5.1.1 - Kernel: SMP 2.4.18-27.8.0.gfs (may be downloaded from Sistina together with the trial distribution), includes all the required drivers. Problems encountered: - Exporting GFS via the kernel-based NFS daemon does not work well (I/Os on NFS clients were ending in error). Sistina was able to reproduce the bug on our setup, and already has partially fixed it – the error rate went down in a visible way. So we are reporting here the results obtained with a generally less-performant but stable user space nfsd. What was measured: 1) Read and Write transfer rates (memory<->GFS file system) for large files 2) Same for the case (memory on NFS client<->GFS exported via NFS) Series 3b - details

Series 3b – GFS native (MB/sec): 

Series 3b – GFS native (MB/sec) NB: - Out of 5 nodes: 1 node was running the lock server process 4 nodes were doing only I/O R / W speed for a single disk array: 123 / 78

Series 3b – GFS exported via NFS (MB/sec): 

Series 3b – GFS exported via NFS (MB/sec) 1 node exporting 3 nodes exporting 4 nodes exporting NB: - User space NFSD was used

Final remarks: 

We are proceeding with the test program. Currently under test: new middleware from CISCO, new tape drive from Sony. We are expecting also a new iSCSI appliance from HP, and an LTO2 drive. We are open for any collaboration. Final remarks

Vendors’ contact info: 

Supermicro servers for Italy E4 Computer Vincenzo Nuti - vincenzo.nuti@e4company.com FC over IP San Valley Systems John McCormack - john.mccormack@sanvalley.com Nishan Systems Stephen Macfall - smacfall@nishansystems.com ACAL FCS Nigel Houghton - nigelhoughton@acalfcs.com CISCO Systems Luciano Pomelli – lpomelli@cisco.com Vendors’ contact info