Well Known Linux Kernel Developer Recommends Against Buying Skylake Systems

[justmy2cents]

you should probably update your article. he edited it and now it specifies this is only relevant to mobile

[rabcor]

Most notably, the fact that it's practically non-existent for anything but heavy-grade server hardware? I know there are one or two companies selling Power-based workstations, but it's not exactly something you can get your hands on easily... or cheaply.

Which is extremely ironic considering how much underachievers these processors are... Lose out to much cheaper and much more widely compatible Xeon any day.

[mjg59]

Er the NUC6i5 has a i5-6260U, proof at http://www.intel.com/content/www/us/...nuc6i5syk.html.

The i5-6260U is a mobile CPU, proof at http://ark.intel.com/products/series...Series#@Mobile.

So what exactly doesn't work?

Oh, that is interesting! Can you post lspci -vvv (run as root)?

[Sloth]

Oh, that is interesting! Can you post lspci -vvv (run as root)?

Here's mine (Dell 5510):

00:00.0 Host bridge: Intel Corporation Skylake Host Bridge/DRAM Registers (rev 07)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Capabilities: [e0] Vendor Specific Information: Len=10 <?>

00:01.0 PCI bridge: Intel Corporation Skylake PCIe Controller (x16) (rev 07) (prog-if 00 [Normal decode])
    Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 120
    Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
    I/O behind bridge: 0000e000-0000efff
    Memory behind bridge: dc000000-dd0fffff
    Prefetchable memory behind bridge: 00000000b0000000-00000000c1ffffff
    Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
    BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
        PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
    Capabilities: [88] Subsystem: Dell Device 06e5
    Capabilities: [80] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Address: 00000000  Data: 0000
    Capabilities: [a0] Express (v2) Root Port (Slot+), MSI 00
        DevCap:    MaxPayload 256 bytes, PhantFunc 0
            ExtTag- RBE+
        DevCtl:    Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
            RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
            MaxPayload 128 bytes, MaxReadReq 128 bytes
        DevSta:    CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
        LnkCap:    Port #2, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <256ns, L1 <8us
            ClockPM- Surprise- LLActRep- BwNot+ ASPMOptComp+
        LnkCtl:    ASPM L0s L1 Enabled; RCB 64 bytes Disabled+ CommClk+
            ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
        LnkSta:    Speed 5GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt+ ABWMgmt+
        SltCap:    AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug- Surprise-
            Slot #1, PowerLimit 75.000W; Interlock- NoCompl+
        SltCtl:    Enable: AttnBtn- PwrFlt- MRL- PresDet- CmdCplt- HPIrq- LinkChg-
            Control: AttnInd Unknown, PwrInd Unknown, Power- Interlock-
        SltSta:    Status: AttnBtn- PowerFlt- MRL- CmdCplt- PresDet+ Interlock-
            Changed: MRL- PresDet+ LinkState-
        RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible-
        RootCap: CRSVisible-
        RootSta: PME ReqID 0000, PMEStatus- PMEPending-
        DevCap2: Completion Timeout: Not Supported, TimeoutDis-, LTR+, OBFF Via WAKE# ARIFwd-
        DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Via WAKE# ARIFwd-
        LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
             Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
             Compliance De-emphasis: -6dB
        LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
             EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
    Capabilities: [100 v1] Virtual Channel
        Caps:    LPEVC=0 RefClk=100ns PATEntryBits=1
        Arb:    Fixed- WRR32- WRR64- WRR128-
        Ctrl:    ArbSelect=Fixed
        Status:    InProgress-
        VC0:    Caps:    PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
            Arb:    Fixed+ WRR32- WRR64- WRR128- TWRR128- WRR256-
            Ctrl:    Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
            Status:    NegoPending+ InProgress-
    Capabilities: [140 v1] Root Complex Link
        Desc:    PortNumber=02 ComponentID=01 EltType=Config
        Link0:    Desc:    TargetPort=00 TargetComponent=01 AssocRCRB- LinkType=MemMapped LinkValid+
            Addr:    00000000fed19000
    Capabilities: [d94 v1] #19
    Kernel driver in use: pcieport

00:02.0 VGA compatible controller: Intel Corporation Device 191d (rev 06) (prog-if 00 [VGA controller])
    Subsystem: Dell Device 06e5
    Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 121
    Region 0: Memory at db000000 (64-bit, non-prefetchable) [size=16M]
    Region 2: Memory at 70000000 (64-bit, prefetchable) [size=256M]
    Region 4: I/O ports at f000 [size=64]
    [virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
    Capabilities: [40] Vendor Specific Information: Len=0c <?>
    Capabilities: [70] Express (v2) Root Complex Integrated Endpoint, MSI 00
        DevCap:    MaxPayload 128 bytes, PhantFunc 0
            ExtTag- RBE+
        DevCtl:    Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
            RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
            MaxPayload 128 bytes, MaxReadReq 128 bytes
        DevSta:    CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
        DevCap2: Completion Timeout: Not Supported, TimeoutDis-, LTR-, OBFF Not Supported
        DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
    Capabilities: [ac] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Address: fee0100c  Data: 4181
    Capabilities: [d0] Power Management version 2
        Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
        Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [100 v1] Process Address Space ID (PASID)
        PASIDCap: Exec+ Priv-, Max PASID Width: 14
        PASIDCtl: Enable- Exec- Priv-
    Capabilities: [200 v1] Address Translation Service (ATS)
        ATSCap:    Invalidate Queue Depth: 00
        ATSCtl:    Enable-, Smallest Translation Unit: 00
    Capabilities: [300 v1] Page Request Interface (PRI)
        PRICtl: Enable- Reset-
        PRISta: RF- UPRGI- Stopped-
        Page Request Capacity: 00008000, Page Request Allocation: 00000000
    Kernel driver in use: i915

00:04.0 Signal processing controller: Intel Corporation Skylake Processor Thermal Subsystem (rev 07)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Interrupt: pin A routed to IRQ 16
    Region 0: Memory at dd320000 (64-bit, non-prefetchable) [size=32K]
    Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
        Address: 00000000  Data: 0000
    Capabilities: [d0] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [e0] Vendor Specific Information: Len=0c <?>
    Kernel driver in use: proc_thermal

00:14.0 USB controller: Intel Corporation Sunrise Point-H USB 3.0 xHCI Controller (rev 31) (prog-if 30 [XHCI])
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
    Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 122
    Region 0: Memory at dd310000 (64-bit, non-prefetchable) [size=64K]
    Capabilities: [70] Power Management version 2
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA PME(D0-,D1-,D2-,D3hot+,D3cold+)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [80] MSI: Enable+ Count=1/8 Maskable- 64bit+
        Address: 00000000feeff00c  Data: 41a2
    Kernel driver in use: xhci_hcd

00:14.2 Signal processing controller: Intel Corporation Sunrise Point-H Thermal subsystem (rev 31)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Interrupt: pin C routed to IRQ 255
    Region 0: Memory at dd334000 (64-bit, non-prefetchable) [size=4K]
    Capabilities: [50] Power Management version 3
        Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [80] MSI: Enable- Count=1/1 Maskable- 64bit-
        Address: 00000000  Data: 0000

00:15.0 Signal processing controller: Intel Corporation Sunrise Point-H Serial IO I2C Controller #0 (rev 31)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 16
    Region 0: Memory at dd333000 (64-bit, non-prefetchable) [size=4K]
    Capabilities: [80] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [90] Vendor Specific Information: Len=14 <?>
    Kernel driver in use: intel-lpss

00:15.1 Signal processing controller: Intel Corporation Sunrise Point-H Serial IO I2C Controller #1 (rev 31)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin B routed to IRQ 17
    Region 0: Memory at dd332000 (64-bit, non-prefetchable) [size=4K]
    Capabilities: [80] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [90] Vendor Specific Information: Len=14 <?>
    Kernel driver in use: intel-lpss

00:16.0 Communication controller: Intel Corporation Sunrise Point-H CSME HECI #1 (rev 31)
    Subsystem: Dell Device 06e5
    Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Interrupt: pin A routed to IRQ 255
    Region 0: Memory at dd331000 (64-bit, non-prefetchable) [disabled] [size=4K]
    Capabilities: [50] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot+,D3cold-)
        Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [8c] MSI: Enable- Count=1/1 Maskable- 64bit+
        Address: 0000000000000000  Data: 0000

00:1c.0 PCI bridge: Intel Corporation Sunrise Point-H PCI Express Root Port #1 (rev f1) (prog-if 00 [Normal decode])
    Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 16
    Bus: primary=00, secondary=02, subordinate=02, sec-latency=0
    I/O behind bridge: 0000f000-00000fff
    Memory behind bridge: dd200000-dd2fffff
    Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
    Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
    BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
        PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
    Capabilities: [40] Express (v2) Root Port (Slot+), MSI 00
        DevCap:    MaxPayload 256 bytes, PhantFunc 0
            ExtTag- RBE+
        DevCtl:    Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
            RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
            MaxPayload 128 bytes, MaxReadReq 128 bytes
        DevSta:    CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
        LnkCap:    Port #1, Speed 8GT/s, Width x1, ASPM L1, Exit Latency L0s <1us, L1 <16us
            ClockPM- Surprise- LLActRep+ BwNot+ ASPMOptComp+
        LnkCtl:    ASPM L1 Enabled; RCB 64 bytes Disabled- CommClk+
            ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
        LnkSta:    Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive+ BWMgmt+ ABWMgmt-
        SltCap:    AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug- Surprise-
            Slot #4, PowerLimit 10.000W; Interlock- NoCompl+
        SltCtl:    Enable: AttnBtn- PwrFlt- MRL- PresDet- CmdCplt- HPIrq- LinkChg-
            Control: AttnInd Unknown, PwrInd Unknown, Power- Interlock-
        SltSta:    Status: AttnBtn- PowerFlt- MRL- CmdCplt- PresDet+ Interlock-
            Changed: MRL- PresDet- LinkState+
        RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible-
        RootCap: CRSVisible-
        RootSta: PME ReqID 0000, PMEStatus- PMEPending-
        DevCap2: Completion Timeout: Range ABC, TimeoutDis+, LTR-, OBFF Not Supported ARIFwd+
        DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled ARIFwd-
        LnkCtl2: Target Link Speed: 8GT/s, EnterCompliance- SpeedDis-
             Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
             Compliance De-emphasis: -6dB
        LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
             EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
    Capabilities: [80] MSI: Enable- Count=1/1 Maskable- 64bit-
        Address: 00000000  Data: 0000
    Capabilities: [90] Subsystem: Dell Device 06e5
    Capabilities: [a0] Power Management version 3
        Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
        Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
    Capabilities: [100 v1] Advanced Error Reporting
        UESta:    DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
        UEMsk:    DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt+ RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
        UESvrt:    DLP+ SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
        CESta:    RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
        CEMsk:    RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
        AERCap:    First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
    Capabilities: [140 v1] Access Control Services
        ACSCap:    SrcValid+ TransBlk+ ReqRedir+ CmpltRedir+ UpstreamFwd- EgressCtrl- DirectTrans-
        ACSCtl:    SrcValid- TransBlk- ReqRedir- CmpltRedir- UpstreamFwd- EgressCtrl- DirectTrans-
    Capabilities: [220 v1] #19
    Kernel driver in use: pcieport

[Sloth]

Here's mine:

http://pastebin.com/wbGmUF6P

[anarki2]

Awesome guy. Explains that Skylake has a feature that Linux doesn't properly implement and then concludes that Skylake is bad. F*ck logic.

[jacob]

Most notably, the fact that it's practically non-existent for anything but heavy-grade server hardware? I know there are one or two companies selling Power-based workstations, but it's not exactly something you can get your hands on easily... or cheaply.

I don't know why it wouldn't be as easy as ordering one online but yes, it's certainly not cheap. Not being Intel compatible also means no games, no Flash support, no Wine and no Windows VM should you need one (and probably a great deal more software compatibility problems, even with open source projects that use some form of JIT, for example). On the other hand, with its sheer horsepower it makes a great development or multimedia workstation. It's also currently the best option for a security critical server.

[Delgarde]

Awesome guy. Explains that Skylake has a feature that Linux doesn't properly implement and then concludes that Skylake is bad. F*ck logic.

Well, apart from the fact that you've completely misrepresented him, sure. There's no conclusion that Skylake is bad - just that you shouldn't buy Skylake mobile parts until these issues are addressed.

[FrankL]

Awesome guy. Explains that Skylake has a feature that Linux doesn't properly implement and then concludes that Skylake is bad. F*ck logic.

Where do you read that? Are we even looking at the same blog post?

EDIT: (not related to the absurd post that was quoted) Reading from the comments on the linked blog, it seems like using a NVMe disk may or may not be involved in the observed issue somehow..

[mjg59]

Here's mine:

http://pastebin.com/wbGmUF6P

Hm. My suspicion is that the mobile Xeons may be closer to the desktop parts than the other mobile ones - the PCH is Sunrise Point-H, which is present on desktop boards, rather than Sunrise Point-LP which is present on mobile. But the difference in PCH may give some insight into what's going on here. I'll dig some more.