Re: [ANNOUNCE] iSCSI enterprise target software

2005-03-02 Thread Vladislav Bolkhovitin
Bryan Henderson wrote: You want to *use* the kernel pagecache as much as you can. No, I really don't. Not always. I can think of only 2 reasons to maximize my use of the kernel pagecache: 1) saves me duplicating code; 2) allows me to share resources (memory and disk bandwidth come to mind)

Re: PING^7 (was Re: [PATCH v2 00/14] Corrections and customization of the SG_IO command whitelist (CVE-2012-4542))

2013-05-24 Thread Vladislav Bolkhovitin
Martin K. Petersen, on 05/22/2013 09:32 AM wrote: Paolo First of all, I'll note that SG_IO and block-device-specific Paolo ioctls both have their place. My usecase for SG_IO is Paolo virtualization, where I need to pass information from the LUN to Paolo the virtual machine with as much

Re: PING^7 (was Re: [PATCH v2 00/14] Corrections and customization of the SG_IO command whitelist (CVE-2012-4542))

2013-05-29 Thread Vladislav Bolkhovitin
Martin K. Petersen, on 05/28/2013 01:25 PM wrote: Vladislav Linux block layer is purely artificial creature slowly Vladislav reinventing wheel creating more problems, than solving. On the contrary. I do think we solve a whole bunch of problems. Vladislav It enforces approach, where often

Re: atomic write T10 standards

2013-07-03 Thread Vladislav Bolkhovitin
Ric Wheeler, on 07/03/2013 11:31 AM wrote: Journals are normally big (128MB or so?) - I don't think that this is unique to xfs. We're mixing a bunch of concepts here. The filesystems have a lot of different requirements, and atomics are just one small part. Creating a new file often uses

Re: [PATCH v2 1/3] scsi_cmnd: Introduce scsi_transfer_length helper

2014-06-24 Thread Vladislav Bolkhovitin
Martin K. Petersen, on 06/23/2014 06:58 PM wrote: Mike == Mike Christie micha...@cs.wisc.edu writes: + unsigned int xfer_len = blk_rq_bytes(scmd-request); Mike Can you do bidi and dif/dix? Nope. Correction: at the moment. There is a proposal of READ GATHERED command, which is

[ANNOUNCE]: SCST 3.0 released

2014-09-20 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce that SCST 3.0 has just been released. This release includes SCST core, target drivers iSCSI-SCST for iSCSI, including iSER support (thanks to Mellanox!), qla2x00t for QLogic Fibre Channel adapters, ib_srpt for InfiniBand SRP, fcst for FCoE and scst_local for local

Re: [ANNOUNCE]: SCST 3.0 released

2014-09-21 Thread Vladislav Bolkhovitin
No, because it's too new, but you can always get it from the git. Or you can use stable Emulex driver for 16Gb connectivity. It's not in the bundle only because of the Emulex policy. Thanks, Vlad On 9/19/2014 23:59, scst.n...@gmail.com wrote: Does 16Gb qla2x00t included? 发自我的小米手机 Vladislav

Re: [Scst-devel] New qla2x00tgt Driver Question

2014-12-03 Thread Vladislav Bolkhovitin
Dr. Greg Wettstein wrote on 12/03/2014 12:46 PM: Secondly, Vlad, we have been running additional testing for the last two days and we have logs from the SCST core which I am including below which suggests that the SCST core target code excessively stalls or mishandles an ABORT while processing

Re: [Scst-devel] New qla2x00tgt Driver Question

2014-12-04 Thread Vladislav Bolkhovitin
Dr. Greg Wettstein wrote on 12/03/2014 11:42 PM: On Dec 3, 8:59pm, Vladislav Bolkhovitin wrote: } Subject: Re: [Scst-devel] New qla2x00tgt Driver Question Dr. Greg Wettstein wrote on 12/03/2014 12:46 PM: Secondly, Vlad, we have been running additional testing for the last two days and we

Re: qla2xxx behavior with changing volumes

2007-09-21 Thread Vladislav Bolkhovitin
Sean Bruno wrote: What is the expected behavior when volumes on a SAN change size and LUN ID order? I've noticed that if a volume changes size, leaves the SAN or changes target ID it isn't auto-magically picked up by a 2.6.18 based system(running CentOS 5). If a new target appears on the SAN

Re: qla2xxx behavior with changing volumes

2007-09-21 Thread Vladislav Bolkhovitin
Vladislav Bolkhovitin wrote: Sean Bruno wrote: What is the expected behavior when volumes on a SAN change size and LUN ID order? I've noticed that if a volume changes size, leaves the SAN or changes target ID it isn't auto-magically picked up by a 2.6.18 based system(running CentOS 5

Re: Target mode support for qlogic chipsets isp2422/2432/5422/5432

2007-10-23 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Tue, 23 Oct 2007 13:47:20 +0530 Thayumanavar Sachithanantham [EMAIL PROTECTED] wrote: Hi All, Does the recent target mode support added for tgt support target mode for qla chipset (qla24xx series)? We've been trying: http://marc.info/?t=11885798674r=1w=2

Re: [Bugme-new] [Bug 9405] New: iSCSI does not implement ordering guarantees required by e.g. journaling filesystems

2007-11-20 Thread Vladislav Bolkhovitin
James Bottomley wrote: On Tue, 2007-11-20 at 19:15 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: I'm not sure your conclusions necessarily follow your data. What was the reason for the TASK ABORTED (I'd guess QErr settings, right)? It was my desire/curiosity during tests

Re: [Bugme-new] [Bug 9405] New: iSCSI does not implement ordering guarantees required by e.g. journaling filesystems

2007-11-20 Thread Vladislav Bolkhovitin
James Bottomley wrote: I'm not sure your conclusions necessarily follow your data. What was the reason for the TASK ABORTED (I'd guess QErr settings, right)? It was my desire/curiosity during tests of SCST (http://scst.sf.net), when it working with several initiators with different

Re: [Bugme-new] [Bug 9405] New: iSCSI does not implement ordering guarantees required by e.g. journaling filesystems

2007-11-20 Thread Vladislav Bolkhovitin
James Bottomley wrote: I'm not sure your conclusions necessarily follow your data. What was the reason for the TASK ABORTED (I'd guess QErr settings, right)? It was my desire/curiosity during tests of SCST (http://scst.sf.net), when it working with several initiators with different

Re: [Bugme-new] [Bug 9405] New: iSCSI does not implement ordering guarantees required by e.g. journaling filesystems

2007-11-21 Thread Vladislav Bolkhovitin
James Bottomley wrote: if you specifically set TAS=1 you're giving up the right to know what caused the command termination. With insufficient information, it's really unsafe to simply retry, which is why the mid layer just returns TASK ABORTED as an error. If you set TAS=0 we'll get a check

Re: Open-FCoE on linux-scsi

2008-01-05 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: What's the general opinion on this? Duplicate code vs. more kernel code? I can see that you're already starting to clean up the code that you ported. Does that mean the duplicate code isn't an issue to you? When we fix bugs in the initiator they're not going to make it

Re: [PATCH 1/6] target/file: Re-enable optional fd_buffered_io=1 operation

2012-10-02 Thread Vladislav Bolkhovitin
Christoph Hellwig, on 10/01/2012 04:46 AM wrote: On Sun, Sep 30, 2012 at 05:58:11AM +, Nicholas A. Bellinger wrote: From: Nicholas Bellingern...@linux-iscsi.org This patch re-adds the ability to optionally run in buffered FILEIO mode (eg: w/o O_DSYNC) for device backends in order to once

[ANNOUNCE]: Emulex SCST support for 16Gb/s FC and FCoE CNAs

2013-09-04 Thread Vladislav Bolkhovitin
I'm glad to announce that SCST support for 16Gb/s FC and FCoE Emulex CNAs is now available as part of the Emulex OneCore Storage SDK tool set based on the Emulex SLI-4 API. Support for 16Gb/s Fibre Channel LPe16000 series and FCoE hardware using target mode versions of the OneConnect FCoE CNAs

Re: Bypass block layer and Fill SCSI lower layer driver queue

2013-09-27 Thread Vladislav Bolkhovitin
Douglas Gilbert, on 09/18/2013 07:07 AM wrote: On 13-09-18 03:58 AM, Jack Wang wrote: On 09/18/2013 08:41 AM, Alireza Haghdoost wrote: Hi I am working on a high throughput and low latency application which does not tolerate block layer overhead to send IO request directly to fiber channel

Re: Is there any plan to support 64bit lun in mainline?

2013-10-15 Thread Vladislav Bolkhovitin
Hannes Reinecke, on 10/14/2013 11:01 PM wrote: And HBAs like lpfc or qla2xxx even have a fast command abort built into the firmware, where the firmware will not even wait for a command abort to hit the wire but rather just disable the exchange internally and return. Doing so is asking for

[ANNOUNCE]: SCST iSER target driver is available for testing

2014-01-29 Thread Vladislav Bolkhovitin
I'm glad to announce that SCST iSER target driver is available for testing from the SCST SVN iser branch. You can download it either by command: $ svn checkout svn://svn.code.sf.net/p/scst/svn/branches/iser iser-scst-branch or by clicking on Download Snapshot button on

[ANNOUNCE]: SCST 2.2 pre-release freeze

2014-05-21 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce SCST 3.0 pre-release code freeze in the SCST SVN branch 3.0.x You can get it by command: $ svn co https://scst.svn.sourceforge.net/svnroot/scst/branches/3.0.x It is going to be released after few weeks of testing, if nothing bad found. SCST is alternative SCSI

Re: [Stgt-devel] Question for pass-through target design

2007-05-07 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: It looks like the pass-through target support is currently broken, at least as I've checked for ibmvstgt, but I think it's a general problem. I wanted to check my assumptions and get ideas. Yeah, unfortunately, it works only with the iSCSI target driver (which runs in

Re: [Stgt-devel] Question for pass-through target design

2007-05-07 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: From: Vladislav Bolkhovitin [EMAIL PROTECTED] Subject: Re: [Stgt-devel] Question for pass-through target design Date: Mon, 07 May 2007 18:24:44 +0400 FUJITA Tomonori wrote: It looks like the pass-through target support is currently broken, at least as I've checked

Re: [Stgt-devel] Question for pass-through target design

2007-05-07 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: From: Vladislav Bolkhovitin [EMAIL PROTECTED] Subject: Re: [Stgt-devel] Question for pass-through target design Date: Mon, 07 May 2007 19:27:23 +0400 FUJITA Tomonori wrote: From: Vladislav Bolkhovitin [EMAIL PROTECTED] Subject: Re: [Stgt-devel] Question for pass

Re: [Stgt-devel] Question for pass-through target design

2007-05-07 Thread Vladislav Bolkhovitin
Vladislav Bolkhovitin wrote: FUJITA Tomonori wrote: From: Vladislav Bolkhovitin [EMAIL PROTECTED] Subject: Re: [Stgt-devel] Question for pass-through target design Date: Mon, 07 May 2007 19:27:23 +0400 FUJITA Tomonori wrote: From: Vladislav Bolkhovitin [EMAIL PROTECTED] Subject: Re: [Stgt

Re: [Scst-devel] Problems with SCST and QLA 2432 FC Cards

2007-05-18 Thread Vladislav Bolkhovitin
sandip shete wrote: Hi, I am working with the SCST 0.9.4 version on linux-2.6.15 with the linux-2.6-qla2xxx-target.patch patch applied. I was using a QLA2312 card on this setup and things were just fine when i used this system as a Target. Now I have switched to a qla2432 card and even though

Re: [Scst-devel] Problems with SCST and QLA 2432 FC Cards

2007-05-18 Thread Vladislav Bolkhovitin
sandip shete wrote: Hi, I wish to develop support for QLA 24xx series. If you already have a partial implementaion of the same, i would like to take it forward. And if there isn't, i would appreciate if you could give me some pointers in that direction. Most probably, the driver by link

Re: [Stgt-devel] Question for pass-through target design

2007-05-25 Thread Vladislav Bolkhovitin
Robert Jennings wrote: * Vladislav Bolkhovitin ([EMAIL PROTECTED]) wrote: Robert Jennings wrote: What I meant that is that the kernel tgt code (scsi_tgt*) receives SCSI commands from one lld and send them to another lld instead of sending them to user space. Although the approach

Re: [Stgt-devel] Question for pass-through target design

2007-06-01 Thread Vladislav Bolkhovitin
Vladislav Bolkhovitin wrote: So, if you need in-kernel pass-through I would suggest you to look at SCST project (http://scst.sf.net), which is currently stable and mature, although also not fully finished yet. It was historically from the very beginning designed for full feature in-kernel pass

Re: [RFC] SCSI target for IBM Power5 LPAR

2005-09-07 Thread Vladislav Bolkhovitin
Dave C Boutcher wrote: On Wed, Sep 07, 2005 at 12:49:32PM +0200, Christoph Hellwig wrote: On Tue, Sep 06, 2005 at 04:28:01PM -0500, Dave C Boutcher wrote: This device driver provides the SCSI target side of the virtual SCSI on IBM Power5 systems. The initiator side has been in mainline for

Re: [RFC] SCSI target for IBM Power5 LPAR/SCST 0.9.3-pre1 published

2005-09-07 Thread Vladislav Bolkhovitin
Mike Christie wrote: Vladislav Bolkhovitin wrote: Sorry, I can see on stgt page only mail lists archive and not from start (from Aug 22). Mike, can I see stgt code and some design description, please? You can send it directly on my e-mail address, if necessary. goto the svn page

Re: [PATCH 2/3] sd: implement START/STOP management

2007-03-22 Thread Vladislav Bolkhovitin
Tejun Heo wrote: Hello, Douglas. Douglas Gilbert wrote: Tejun, I note at this point that the IMMED bit in the START STOP UNIT cdb is clear. [The code might note that as well.] All SCSI disks that I have seen, implement the IMMED bit and according to the SAT standard, so should SAT layers like

Re: [PATCH 2/3] sd: implement START/STOP management

2007-03-22 Thread Vladislav Bolkhovitin
Henrique de Moraes Holschuh wrote: On Thu, 22 Mar 2007, Vladislav Bolkhovitin wrote: Seems, there is another way of doing a bank spin up / spin down: doing it in two passes. On the first pass START_STOP will be issued with IMMED=1 on all devices, then on the second pass START_STOP

Re: Performance of SCST versus STGT

2008-01-17 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Thu, 17 Jan 2008 10:27:08 +0100 Bart Van Assche [EMAIL PROTECTED] wrote: Hello, I have performed a test to compare the performance of SCST and STGT. Apparently the SCST target implementation performed far better than the STGT target implementation. This makes me

Re: Performance of SCST versus STGT

2008-01-17 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Thu, 17 Jan 2008 12:48:28 +0300 Vladislav Bolkhovitin [EMAIL PROTECTED] wrote: FUJITA Tomonori wrote: On Thu, 17 Jan 2008 10:27:08 +0100 Bart Van Assche [EMAIL PROTECTED] wrote: Hello, I have performed a test to compare the performance of SCST and STGT

Re: [Scst-devel] [Stgt-devel] Performance of SCST versus STGT

2008-01-17 Thread Vladislav Bolkhovitin
Robin Humble wrote: On Thu, Jan 17, 2008 at 01:34:46PM +0300, Vladislav Bolkhovitin wrote: Hmm, I can't find which IB hardware did he use and it's declared Gbps speed. He declared only Mellanox 4X SDR, switch. What does it mean? SDR is 10Gbit carrier, at most about ~900MB/s data rate. DDR

Re: Performance of SCST versus STGT

2008-01-17 Thread Vladislav Bolkhovitin
Erez Zilber wrote: FUJITA Tomonori wrote: On Thu, 17 Jan 2008 12:48:28 +0300 Vladislav Bolkhovitin [EMAIL PROTECTED] wrote: FUJITA Tomonori wrote: On Thu, 17 Jan 2008 10:27:08 +0100 Bart Van Assche [EMAIL PROTECTED] wrote: Hello, I have performed a test to compare

Re: Performance of SCST versus STGT

2008-01-18 Thread Vladislav Bolkhovitin
Pete Wyckoff wrote: I have performed a test to compare the performance of SCST and STGT. Apparently the SCST target implementation performed far better than the STGT target implementation. This makes me wonder whether this is due to the design of SCST or whether STGT's performance can be

Re: Performance of SCST versus STGT

2008-01-21 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 18, 2008 1:08 PM, Vladislav Bolkhovitin [EMAIL PROTECTED] wrote: [ ... ] So, seems I understood your slides correctly: the more valuable data for our SCST SRP vs STGT iSER comparison should be on page 26 for 1 command read (~480MB/s, i.e. ~60% from Bart's result

Re: Performance of SCST versus STGT

2008-01-22 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: The big problem of stgt iSER is disk I/Os (move data between disk and page cache). We need a proper asynchronous I/O mechanism, however, Linux doesn't provide such and we use a workaround, which incurs large latency. I guess, we cannot solve this until syslets is merged

Re: Performance of SCST versus STGT

2008-01-22 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 17, 2008 6:45 PM, Pete Wyckoff [EMAIL PROTECTED] wrote: There's nothing particularly stunning here. Suspect Bart has configuration issues if not even IPoIB will do 100 MB/s. By this time I found out that the BIOS of the test systems (Intel Server Board

Re: Performance of SCST versus STGT

2008-01-22 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Tue, 22 Jan 2008 14:33:13 +0300 Vladislav Bolkhovitin [EMAIL PROTECTED] wrote: FUJITA Tomonori wrote: The big problem of stgt iSER is disk I/Os (move data between disk and page cache). We need a proper asynchronous I/O mechanism, however, Linux doesn't provide

Re: Performance of SCST versus STGT

2008-01-22 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 22, 2008 12:33 PM, Vladislav Bolkhovitin [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: What are the new SRPT/iSER numbers? You can find the new performance numbers below. These are all numbers for reading from the remote buffer cache, no actual disk reads

Re: Integration of SCST in the mainstream Linux kernel

2008-01-23 Thread Vladislav Bolkhovitin
about the design of SCST can be found here: http://scst.sourceforge.net/doc/scst_pg.html. My impression is that both the STGT and SCST projects are well designed, well maintained and have a considerable user base. According to the SCST maintainer (Vladislav Bolkhovitin), SCST is superior to STGT

Re: Performance of SCST versus STGT

2008-01-24 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 24, 2008 8:06 AM, Robin Humble [EMAIL PROTECTED] wrote: On Tue, Jan 22, 2008 at 01:32:08PM +0100, Bart Van Assche wrote: . . . STGT read

Re: [Stgt-devel] Performance of SCST versus STGT

2008-01-24 Thread Vladislav Bolkhovitin
Robin Humble wrote: On Thu, Jan 24, 2008 at 11:36:45AM +0100, Bart Van Assche wrote: On Jan 24, 2008 8:06 AM, Robin Humble [EMAIL PROTECTED] wrote: On Tue, Jan 22, 2008 at 01:32:08PM +0100, Bart Van Assche wrote:

Re: Performance of SCST versus STGT

2008-01-24 Thread Vladislav Bolkhovitin
Robin Humble wrote: On Thu, Jan 24, 2008 at 02:10:06PM +0300, Vladislav Bolkhovitin wrote: On Jan 24, 2008 8:06 AM, Robin Humble [EMAIL PROTECTED] wrote: how are write speeds with SCST SRP? for some kernels and tests tgt writes at 2x the read speed. There is a fundamental difference

Re: Performance of SCST versus STGT

2008-01-24 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 24, 2008 8:06 AM, Robin Humble [EMAIL PROTECTED] wrote: On Tue, Jan 22, 2008 at 01:32:08PM +0100, Bart Van Assche wrote: . . . STGT read

Re: Integration of SCST in the mainstream Linux kernel

2008-01-30 Thread Vladislav Bolkhovitin
James Bottomley wrote: The two target architectures perform essentially identical functions, so there's only really room for one in the kernel. Right at the moment, it's STGT. Problems in STGT come from the user-kernel boundary which can be mitigated in a variety of ways. The fact that the

Re: Integration of SCST in the mainstream Linux kernel

2008-01-30 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Tue, 29 Jan 2008 13:31:52 -0800 Roland Dreier [EMAIL PROTECTED] wrote: . . STGT read SCST read.STGT read SCST read. . . performance performance . performance performance . .

Re: Integration of SCST in the mainstream Linux kernel

2008-01-30 Thread Vladislav Bolkhovitin
FUJITA Tomonori wrote: On Wed, 30 Jan 2008 09:38:04 +0100 Bart Van Assche [EMAIL PROTECTED] wrote: On Jan 30, 2008 12:32 AM, FUJITA Tomonori [EMAIL PROTECTED] wrote: iSER has parameters to limit the maximum size of RDMA (it needs to repeat RDMA with a poor configuration)? Please specify

Re: Integration of SCST in the mainstream Linux kernel

2008-01-31 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 31, 2008 2:25 PM, Nicholas A. Bellinger [EMAIL PROTECTED] wrote: Since this particular code is located in a non-data path critical section, the kernel vs. user discussion is a wash. If we are talking about data path, yes, the relevance of DD tests in kernel

Re: [Scst-devel] Integration of SCST in the mainstream Linux kernel

2008-02-01 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Jan 31, 2008 5:25 PM, Joe Landman [EMAIL PROTECTED] wrote: Vladislav Bolkhovitin wrote: Actually, I don't know what kind of conclusions it is possible to make from disktest's results (maybe only how throughput gets bigger or slower with increasing number of threads

Re: [Scst-devel] Integration of SCST in the mainstream Linux kernel

2008-02-01 Thread Vladislav Bolkhovitin
Vladislav Bolkhovitin wrote: Bart Van Assche wrote: On Jan 31, 2008 5:25 PM, Joe Landman [EMAIL PROTECTED] wrote: Vladislav Bolkhovitin wrote: Actually, I don't know what kind of conclusions it is possible to make from disktest's results (maybe only how throughput gets bigger or slower

Re: [Scst-devel] Integration of SCST in the mainstream Linux kernel

2008-02-01 Thread Vladislav Bolkhovitin
David Dillow wrote: On Thu, 2008-01-31 at 18:08 +0100, Bart Van Assche wrote: If anyone has a suggestion for a better test than dd to compare the performance of SCSI storage protocols, please let it know. xdd on /dev/sda, sdb, etc. using -dio to do direct IO seems to work decently, though

Re: Integration of SCST in the mainstream Linux kernel

2008-02-04 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: On Feb 4, 2008 1:27 PM, Vladislav Bolkhovitin [EMAIL PROTECTED] wrote: So, James, what is your opinion on the above? Or the overall SCSI target project simplicity doesn't matter much for you and you think it's fine to duplicate Linux page cache in the user space to keep

Re: Integration of SCST in the mainstream Linux kernel

2008-02-04 Thread Vladislav Bolkhovitin
James Bottomley wrote: So, James, what is your opinion on the above? Or the overall SCSI target project simplicity doesn't matter much for you and you think it's fine to duplicate Linux page cache in the user space to keep the in-kernel part of the project as small as possible? The answers

Re: Integration of SCST in the mainstream Linux kernel

2008-02-04 Thread Vladislav Bolkhovitin
James Bottomley wrote: On Mon, 2008-02-04 at 20:16 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: So, James, what is your opinion on the above? Or the overall SCSI target project simplicity doesn't matter much for you and you think it's fine to duplicate Linux page cache

Re: Integration of SCST in the mainstream Linux kernel

2008-02-04 Thread Vladislav Bolkhovitin
Vladislav Bolkhovitin wrote: James Bottomley wrote: The two target architectures perform essentially identical functions, so there's only really room for one in the kernel. Right at the moment, it's STGT. Problems in STGT come from the user-kernel boundary which can be mitigated in a variety

Re: Integration of SCST in the mainstream Linux kernel

2008-02-04 Thread Vladislav Bolkhovitin
James Bottomley wrote: On Mon, 2008-02-04 at 20:56 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: On Mon, 2008-02-04 at 20:16 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: So, James, what is your opinion on the above? Or the overall SCSI target project

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
Erez Zilber wrote: Bart Van Assche wrote: As you probably know there is a trend in enterprise computing towards networked storage. This is illustrated by the emergence during the past few years of standards like SRP (SCSI RDMA Protocol), iSCSI (Internet SCSI) and iSER (iSCSI Extensions for

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
Jeff Garzik wrote: iSCSI is way, way too complicated. I fully agree. From one side, all that complexity is unavoidable for case of multiple connections per session, but for the regular case of one connection per session it must be a lot simpler. Actually, think about those multiple

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
Jeff Garzik wrote: Alan Cox wrote: better. So for example, I personally suspect that ATA-over-ethernet is way better than some crazy SCSI-over-TCP crap, but I'm biased for simple and low-level, and against those crazy SCSI people to begin with. Current ATAoE isn't. It can't support NCQ. A

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
Linus Torvalds wrote: I'd assumed the move was primarily because of the difficulty of getting correct semantics on a shared filesystem .. not even shared. It was hard to get correct semantics full stop. Which is a traditional problem. The thing is, the kernel always has some internal

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
James Bottomley wrote: On Mon, 2008-02-04 at 21:38 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: On Mon, 2008-02-04 at 20:56 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote: On Mon, 2008-02-04 at 20:16 +0300, Vladislav Bolkhovitin wrote: James Bottomley wrote

Re: Integration of SCST in the mainstream Linux kernel

2008-02-05 Thread Vladislav Bolkhovitin
Linus Torvalds wrote: So just going by what has happened in the past, I'd assume that iSCSI would eventually turn into connecting/authentication in user space with data transfers in kernel space. This is exactly how iSCSI-SCST (iSCSI target driver for SCST) is implemented, credits to IET and

Re: Integration of SCST in the mainstream Linux kernel

2008-02-06 Thread Vladislav Bolkhovitin
James Bottomley wrote: On Tue, 2008-02-05 at 21:59 +0300, Vladislav Bolkhovitin wrote: Hmm, how can one write to an mmaped page and don't touch it? I meant from user space ... the writes are done inside the kernel. Sure, the mmap() approach agreed to be unpractical, but could you

Re: Integration of SCST in the mainstream Linux kernel

2008-02-07 Thread Vladislav Bolkhovitin
Bart Van Assche wrote: Since the focus of this thread shifted somewhat in the last few messages, I'll try to summarize what has been discussed so far: - There was a number of participants who joined this discussion spontaneously. This suggests that there is considerable interest in networked

Re: Integration of SCST in the mainstream Linux kernel

2008-02-08 Thread Vladislav Bolkhovitin
[EMAIL PROTECTED] wrote: On Thu, 7 Feb 2008, Vladislav Bolkhovitin wrote: Bart Van Assche wrote: - It has been discussed which iSCSI target implementation should be in the mainstream Linux kernel. There is no agreement on this subject yet. The short-term options are as follows: 1) Do

Re: Integration of SCST in the mainstream Linux kernel

2008-02-08 Thread Vladislav Bolkhovitin
Luben Tuikov wrote: Is there an open iSCSI Target implementation which does NOT issue commands to sub-target devices via the SCSI mid-layer, but bypasses it completely? What do you mean? To call directly low level backstorage SCSI drivers queuecommand() routine? What are advantages of it?

Re: Integration of SCST in the mainstream Linux kernel

2008-02-08 Thread Vladislav Bolkhovitin
Nicholas A. Bellinger wrote: On Thu, 2008-02-07 at 12:37 -0800, Luben Tuikov wrote: Is there an open iSCSI Target implementation which does NOT issue commands to sub-target devices via the SCSI mid-layer, but bypasses it completely? Luben Hi Luben, I am guessing you mean futher down

Re: Integration of SCST in the mainstream Linux kernel

2008-02-08 Thread Vladislav Bolkhovitin
Nicholas A. Bellinger wrote: - It has been discussed which iSCSI target implementation should be in the mainstream Linux kernel. There is no agreement on this subject yet. The short-term options are as follows: 1) Do not integrate any new iSCSI target implementation in the mainstream Linux

Re: Integration of SCST in the mainstream Linux kernel

2008-02-11 Thread Vladislav Bolkhovitin
Luben Tuikov wrote: Is there an open iSCSI Target implementation which does NOT issue commands to sub-target devices via the SCSI mid-layer, but bypasses it completely? What do you mean? To call directly low level backstorage SCSI drivers queuecommand() routine? What are advantages of

T10-PI: Getting failed tag info

2014-12-10 Thread Vladislav Bolkhovitin
Hi, We are currently developing a SCSI target system with T10-PI. We are using block integrity interface and found a problem that this interface fundamentally can not pass Oracle T10-PI certification tests. Those tests require to receive on the initiator side information about which particular

Re: T10-PI: Getting failed tag info

2014-12-12 Thread Vladislav Bolkhovitin
Martin K. Petersen wrote on 12/11/2014 07:12 PM: Vlad == Vladislav Bolkhovitin v...@vlnb.net writes: Vlad We are currently developing a SCSI target system with T10-PI. We Vlad are using block integrity interface and found a problem that this Vlad interface fundamentally can not pass Oracle T10

Re: [LSF/MM TOPIC] iSCSI MQ adoption via MCS discussion

2015-01-13 Thread Vladislav Bolkhovitin
Sagi Grimberg wrote on 01/08/2015 05:45 AM: RFC 3720 namely requires that iSCSI numbering is session-wide. This means maintaining a single counter for all MC/S sessions. Such a counter would be a contention point. I'm afraid that because of that counter performance on a multi-socket initiator

[ANNOUNCE]: SCST 3.0.1 released

2015-02-24 Thread Vladislav Bolkhovitin
I'm glad to announce that maintenance update for SCST and its drivers 3.0.1 has just been released and ready for download from http://scst.sourceforge.net/downloads.html. All SCST users are encouraged to update. SCST is alternative SCSI target stack for Linux. SCST allows creation of

Re: [ANNOUNCE]: SCST 3.1 pre-release freeze

2015-11-06 Thread Vladislav Bolkhovitin
Hi, Bike & Snow wrote on 11/06/2015 10:55 AM: > Hello Vlad > > Excellent news on all the updates. > > Regarding this: > - QLogic target driver has been significantly improved. > > Does that mean I should stop building the QLogic target driver from here? > git://git.qlogic.com/scst-qla2xxx.git

[ANNOUNCE]: SCST 3.1 pre-release freeze

2015-11-05 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce SCST 3.1 pre-release code freeze in the SCST SVN branch 3.0.x. You can get it by command: $ svn co https://scst.svn.sourceforge.net/svnroot/scst/branches/3.1.x It is going to be released after few weeks of testing, if no significant issues found. Highlights for

Re: [LSF/MM TOPIC] LIO/SCST Merger

2016-01-28 Thread Vladislav Bolkhovitin
Nicholas A. Bellinger wrote on 01/27/2016 10:36 PM: > On Wed, 2016-01-27 at 09:54 -0800, Bart Van Assche wrote: >> Last year, during the 2015 LSF/MM summit, it has been decided that the >> LIO/SCST merger project should proceed by sending the functionality >> upstream that is present in SCST but

[ANNOUNCE]: SCST 3.1 release

2016-01-21 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce that SCST version 3.1 has just been released and available for download from http://scst.sourceforge.net/downloads.html. Highlights for this release: - Cluster support for SCSI reservations. This feature is essential for initiator-side clustering approaches based

[ANNOUNCE]: SCST 3.2 pre-release freeze

2016-08-02 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce SCST 3.2 pre-release code freeze in the SCST SVN branch 3.2.x. You can get it by command: $ svn co https://scst.svn.sourceforge.net/svnroot/scst/branches/3.2.x It is going to be released after few weeks of testing, if no significant issues found. SCST is

[ANNOUNCE]: SCST 3.2 released

2016-12-15 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce SCST 3.2 has just been released You can download it from http://scst.sourceforge.net/downloads.html SCST is alternative SCSI target stack for Linux. SCST allows creation of sophisticated storage devices, which can provide advanced functionality, like replication,

[ANNOUNCE]: SCST 3.3 pre-release freeze

2017-08-31 Thread Vladislav Bolkhovitin
Hi All, I'm glad to announce SCST 3.3 pre-release code freeze in the SCST SVN branch 3.3.x. You can get it by command: $ svn co https://scst.svn.sourceforge.net/svnroot/scst/branches/3.3.x It is going to be released after few weeks of testing, if no significant issues found. SCST is