Recent content by orki

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    Hard disk enclosure recommendations after Silverstone RS-431U failure

    My Teratrend-branded Silverstone RS-431U hard disk enclosure won't power on after it was powered down to be moved to a new location on the rack. Not powering on has been a problem with this device several times in the past. However, my usual solution of "unplug the power cord from the outlet...
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    HP 2530 LLC broadcast every 60 seconds

    This is the HP switch stacking protocol. You can disable it by going into configuration mode and running no stack, and do not forget to call write memory.
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    HP Z840 bios update

    That's the basic conundrum. As the machine will be used primarily as a compilation server, Spectre/Meltdown fixes are not particularly important, especially if they cause performance slowdowns.
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    HP Z840 bios update

    I recently bought a HP Z840 off the bay which came with a fairly old version of BIOS. HP's website does provide the latest BIOS updates. Is there any reason not to apply the latest update? Also, is this the right forum to post this question?
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    FS: v3 Xeon, SSDs, Networking, Misc

    Received 6x 16 GB Samsung 2Rx4 PC4-2400T ECC DIMM (M393A2G40DB1) from @semidetached . Well packed, prompt shipping and great pricing. Thanks.
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    Delay (HP) L2 switch boot up until DHCP available

    My main router (running either VyOS or OpnSense) should assign IP addresses (via DHCP) to the various L2 switches. This works fine usually except when there has been a power outage. When power is restored, all of my L2 switches (couple of HP 2530-24G and one Netgear GS116E) boot up well before...
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    Compilation server

    I don't really need or want the NVidia Quadro K5000; it appears to sell for 150-200 USD on evilBay, about the same as 64GB of the right kind of RAM. It'd be nice to figure out a way to barter it for 64GB DDR4-2400 RDIMMs. Other than the forums here, is there anywhere else such a swap might be...
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    Compilation server

    I ran out of patience and decided to tempt fate by buying HP Z840 | 8 GB / 1.00 TB | DUAL Xeon E5-2680 v4 | K5000 workstation from a seller with only a 98.9% positive rating of evilBay for a total of about 550 USD (including taxes). Unless the description is grossly wrong, this is a Broadwell-EP...
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    Compilation server

    The valgrind results are more complicated than I expected. The issue is that there is an L3 cache miss rate of 0.1% rd and 0.6% wr, which is not realistic; valgrind modeled the entire L3 cache for the Xeon Gold 6254. When running multiple compilations in parallel, this will clearly not be true...
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    Compilation server

    This is similar to RTM's idea, unless I'm mising something, for roughly the same cost. In terms of both memory bandwidth and CPU performance, the Dell T7810 workstation with dual cores would have roughly double the performance at the cost of (much?) higher power consumption. The advantage of the...
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    Compilation server

    My code does not have much pointer indirection, precisely to avoid this problem. The description above was of the kernel (which was UhClem's comparison above), whose APIs tend to use a lot of pointer indirections. The speed of compiled binaries is a fun optimization problem, which is the reason...
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    Compilation server

    What is the reason for recommending DDR4? Is it because of future proofing against memory bandwidth issues?
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    Compilation server

    This is a nice idea. I had not considered workstations, in spite of using a Dell Precision 5610 as my desktop and jump server at work. Is replacing my desktop machine with such a workstation a better idea than a separate compilation server? My (likely flawed) thought process behind a separate...
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    Compilation server

    Thank you for this comment. You are answering the heart of my question.
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    Compilation server

    The kernel is a fairly small (but very sexy) project when compiling for a single platform; it uses a lot of pointer indirection (for good reasons) which lets it be generic and be able to compile translation units independently. If the output of the kernel menu's configuration system could be...