SysRQ via serial console doesn't work for VMWare guests

Hi, I have tried to utilize SysRQ via serial console in VMWare environment: >From what I've seen RS-232 Break + just doesn't work for 3.13.1 for VMWare guests: [root@dca-eccs-sbx-db2 ~]# cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:03F8 irq:4 tx:10034 rx:1 RTS

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Cristoph, On 8 January 2014 16:03, Christoph Hellwig wrote: > On Tue, Jan 07, 2014 at 08:37:23PM +0200, Sergey Meirovich wrote: >> Actually my initial report (14.67Mb/sec 3755.41 Requests/sec) was about ext4 >> However I have tried XFS as well. It was a bit slower t

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

On 10 January 2014 16:32, Sergey Meirovich wrote: > Hi Jan, > > On 10 January 2014 12:48, Jan Kara wrote: >> On Fri 10-01-14 12:36:22, Sergey Meirovich wrote: >>> Hi Jan, >>> >>> On 10 January 2014 11:36, Jan Kara wrote: >>>

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Jan, On 10 January 2014 12:48, Jan Kara wrote: > On Fri 10-01-14 12:36:22, Sergey Meirovich wrote: >> Hi Jan, >> >> On 10 January 2014 11:36, Jan Kara wrote: >> > On Thu 09-01-14 12:11:16, Sergey Meirovich wrote: >> ... >> >> I've done

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Jan, On 10 January 2014 11:36, Jan Kara wrote: > On Thu 09-01-14 12:11:16, Sergey Meirovich wrote: ... >> I've done preallocation on fnic/XtremIO as Christoph suggested. >> >> [root@dca-poc-gtsxdb3 mnt]# sysbench --max-requests=0 >> --file-extra-flags=direc

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi, On 9 January 2014 23:26, Sergey Meirovich wrote: > Hi Duglas, > > On 9 January 2014 21:54, Douglas Gilbert wrote: >> On 14-01-08 08:57 AM, Sergey Meirovich wrote: > ... >>> >>> The strangest thing to me that this is the problem with sequential >>&g

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Duglas, On 9 January 2014 21:54, Douglas Gilbert wrote: > On 14-01-08 08:57 AM, Sergey Meirovich wrote: ... >> >> The strangest thing to me that this is the problem with sequential >> write. For example the fnic one machine is zoned to EMC XtremIO and >> had r

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Jan, On 8 January 2014 22:55, Jan Kara wrote: > >> So far I've seen so massive degradation only in SAN environment. I >> started my investigation with RHEL6.5 kernel so below table is from it >> but the trend is the same as for mainline it seems. >> >> Chunk size Bandwidth MiB/s >>

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

On 8 January 2014 17:26, Christoph Hellwig wrote: > > On my laptop SSD I get the following results (sometimes up to 200MB/s, > sometimes down to 100MB/s, always in the 40k to 50k IOps range): > > time elapsed (sec.):5 > bandwidth (MiB/s): 160.00 > IOps: 40960.00 Any dir

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Christoph, On 8 January 2014 16:03, Christoph Hellwig wrote: > On Tue, Jan 07, 2014 at 08:37:23PM +0200, Sergey Meirovich wrote: >> Actually my initial report (14.67Mb/sec 3755.41 Requests/sec) was about ext4 >> However I have tried XFS as well. It was a bit slower t

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi James, On 7 January 2014 22:57, James Smart wrote: > Sergey, > > The Thor chipset is a bit old - a 4Gig adapter. Most of our performance > improvements, including parallelization, have gone into the 8G and 16G > adapters. But you still should have seen significantly beyond what you > reported

Re: Terrible performance of sequential O_DIRECT 4k writes in SAN environment. ~3 times slower then Solars 10 with the same HBA/Storage.

Hi Christoph, On 7 January 2014 17:58, Christoph Hellwig wrote: > On Mon, Jan 06, 2014 at 09:10:32PM +0100, Jan Kara wrote: >> This is likely a problem of Linux direct IO implementation. The thing is >> that in Linux when you are doing appending direct IO (i.e., direct IO which >> changes file

Re: Linux 3.9.8

On 30 June 2013 03:33, Greg KH wrote: > On Sat, Jun 29, 2013 at 11:58:04PM +0300, Sergey Meirovich wrote: >> Hi, >> >> On 27 June 2013 20:59, Greg KH wrote: >> > I'm announcing the release of the 3.9.8 kernel. >> > >> > All users of the 3.9 k

Re: Linux 3.10-rc7

On 30 June 2013 01:13, Linus Torvalds wrote: > On Sat, Jun 29, 2013 at 2:07 PM, Sergey Meirovich > wrote: >>> (and possibly the >>> mkregtable binary) and trying again might fix it. >> >> Removing mkregtable has indeed the compile issue for me. Thanks! >

Re: Linux 3.10-rc7

Hi Linus, On 29 June 2013 21:11, Linus Torvalds wrote: > On Sat, Jun 29, 2013 at 8:05 AM, Sergey Meirovich > wrote: >> >> 3.10-rc7 doesn't compile for me >> >> rathamahata@piledriver /usr/local/src/linux-3.10-rc7 $ make -j1 bzImage >> modules >>

Re: Linux 3.9.8

Hi, On 27 June 2013 20:59, Greg KH wrote: > I'm announcing the release of the 3.9.8 kernel. > > All users of the 3.9 kernel series must upgrade. I've got issues with my radeon ("01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Thames [Radeon HD 7500M/7600M Series]") APU

Re: Linux 3.7.8

On 29 June 2013 23:50, Sergey Meirovich wrote: > Hi, > > On 14 February 2013 21:12, Greg KH wrote: >> I'm announcing the release of the 3.7.8 kernel. Please ignore - this is about 3.9.8 kernel > > I've got issues with my radeon GPU on 3.7.8 > ... > [ 20

Re: Linux 3.7.8

Hi, On 14 February 2013 21:12, Greg KH wrote: > I'm announcing the release of the 3.7.8 kernel. I've got issues with my radeon GPU on 3.7.8 ... [ 20.944106] BUG: unable to handle kernel NULL pointer dereference at 01f8 [ 20.945753] IP: [] radeon_vm_bo_add+0xb3/0x110 [ 20.946498

Re: 3.10-rc4: mtrr_cleanup: can not find optimal value, please specify mtrr_gran_size/mtrr_chunk_size

Hi, On 10 June 2013 21:28, Yinghai Lu wrote: > On Mon, Jun 10, 2013 at 11:00 AM, Sergey Meirovich > wrote: > >> 3.10-rc5 with patches has curred error messages in dmesg but MTRRs >> still do not cover my entire memory (7748Mb) or anything close to it >>

Re: 3.10-rc4: mtrr_cleanup: can not find optimal value, please specify mtrr_gran_size/mtrr_chunk_size

, size= 4096MB, count=1: write-back > reg03: base=0x20000 ( 8192MB), size= 1024MB, count=1: write-back > reg04: base=0x0d000 ( 3328MB), size= 256MB, count=1: write-combining > > which is the same like on 3.8.13 > > > Thanks ! > > Matt > > On Mon, Jun 10, 201

Re: [PATCH v2 2/2] x86, range: Do not add new blank slot with add_range_with_merge

Hi, On 10 June 2013 09:29, Yinghai Lu wrote: > Joshua reported: Commit cd7b304dfaf1 (x86, range: fix missing merge > during add range) broke mtrr cleanup on his setup in 3.9.5. > corresponding commit in upstream is fbe06b7bae7c. > > The reason is add_range_with_merge could generate blank spot. >

Re: 3.10-rc4: mtrr_cleanup: can not find optimal value, please specify mtrr_gran_size/mtrr_chunk_size

Hi, On 5 June 2013 02:08, Matt wrote: > Hi everyone, > > > I noticed today the following error messages in /var/log/kern.log : > > > Jun 5 00:26:48 localhost kernel: [0.00] MTRR default type: uncachable > Jun 5 00:26:48 localhost kernel: [0.00] MTRR fixed ranges enabled: > Jun