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Comment Checking the wrong thing in a not great place? (Score 1) 136 136

First up lkml.org is a third party site that hosts Linux kernel mailing list archives on a website. Regular Linux kernel mail isn't actually sent from it (I believe that's done by vger) so we're looking up the email reputation for the wrong IP...

Secondly UCEPROTECT is a very aggressive blacklist which states upfront they will block people who they believe are in the vicinity of people who the judge to be sending them spam. It's not the be and end all though and on one server I looked some time ago it's effectiveness was surpassed by other blacklists (here's someone else's old DNS blacklist comparison for 2014). In general I prefer more conservative tools like senderbase when trying to work out an IPs mail reputation.

For what it's worth I've also seen GMail incorrectly mark mails sent to the fio mailing list (which is also managed by vger) as spam and in that case it was purely down to mail being proxied through the list which was a place that didn't match the sender's DMARC records. Most of the time GMail was getting the marking of spam right though (even for mailing list mails)...

Comment Article author wasn't using queued TRIM (Score 1) 182 182

The article now contains an update stating that queued TRIM was not involved (that ordinary TRIM was to blame is also mentioned in the author's Hackers News comment) only ordinary TRIM. It also appears that the company's drives were enterprise Samsung PROs.

Comment systemd was in native mode for the first two (Score 1) 442 442

Anecdotes 1 + 2 were running in native mode because it was initially a fresh install that was then switched sysvinit-core. Anecdote 3 I don't know (most likely compatability mode as it was several years ago). Even if all the anecdotes were only running in compatibility mode the results show systemd finishing quicker...

Does the above make things any better and how fast do you expect things to go when you're bottlenecked on I/O throughput? Is 15 seconds for a hard disk or 4(!) seconds for a RAM disk so bad?

Comment Re:Systemd vs sysinit boot speed anecodote (Score 1) 442 442

The NFS mounts were always mounted at boot and not on demand both before and after systemd. The difference was that because there were multiple NFS mounts only proceeded in serial before the switch. After the switch the waiting of the mounts happened in parallel not just with each other but other services too. Yes it is entirely pathological but it really happened (and presumably other parallel inits would have solved it this way too).

For what it's worth I have an EeePC too. The default Xandros distro was a classic case of not running very much because it was highly custom (e.g. no printing, no mdns, kernel doesn't have to probe for all different kinds of hardware, hotplug of USB devices, io scheduler set to deadline etc) and thus was fast - I would always expect it to outperform a generic "full fat" Linux distribution. I'd expect your FreeBSD to beat my current XFCE Ubuntu setup too because I bet you can get start less. With lots of hand tweaks the boot speed to an XFCE desktop on my EeePC 900 is still 17 seconds...

Comment Systemd vs sysinit boot speed anecodote (Score 4, Informative) 442 442

Anecdote 1: I've just timed a Debian Jessie single CPU hard disk based VM install with BTRFS as the filesystem, a GNOME 3 desktop where the user is auto logged in boot and where an autostart script records the time. Here are my rough systemd and sysvinit results (times are from after the kernel core finished to when the GNOME script ran):
sysvinit (apt-get install sysvinit-core)
First boot: 20 seconds
Second boot: 18 seconds
Third boot: 19 seconds
systemd (apt-get remove sysvinit-core)
First boot: 15 seconds
Second boot: 16 seconds
Third boot: 15 seconds

sysvinit averages 19 seconds, systemd averages 15.33 seconds. In this case it does appear that systemd booted the system faster.

Anecdote 2: Same as above but where the VM's disk is sitting wholly in RAM. Time for sysvinit dropped to 5 seconds and the time for systemd dropped to 4 seconds.

My personal guess is that the more you are running, the slower the disk the more likely systemd is to benefit you. You don't say how you did your comparison though or what type your "disks" were. If your comparison was between different versions of Linux distro then it could simply be that the previous version did less (which is always the fastest way to boot)...

Another anecdote: a few years back I saw Slackware systems at a University converted over to systemd. Boot times (which involved waiting for multiple NFS mounts) went from over three minutes to down to less than a minute because more of the waiting was done in parallel.

Comment Unusual way of looking at it (Score 1) 162 162

While my interaction with storage is "how long did it take for this operation to finish" the answer to that can vary dramatically on a hard disk depending on type and frequency of I/O I was doing (whereas the difference between best and worst values narrows with flash).

Your table doesn't capture the difference in wait time between reading only reading a 1GByte ISO in big chunks that's been laid out sequentially and serving up multiple torrents from big files that are over different parts of the disk simultaneously. You aren't always in the worst case and if the data is already cached in RAM you may be totally unable to perceive a difference because the waiting was decoupled from the request.

Telling people that "wait time" describes what they're seeing feels like it's trying to push latency and throughput into one number when both need to be distributions describing particular patterns of (potentially parallel) I/O and that's not even getting into queue depth. I guess there are parallels to telling people to describe things in terms of load average too...

Patents

Patent Trolls On the Run But Not Vanquished Yet 56 56

snydeq writes Strong legislation that will weaken the ability of the trolls to shake down innovators is likely to pass Congress, but more should be done, writes InfoWorld's Bill Snyder. "The Innovation Act isn't an ideal fix for the program patent system. But provisions in the proposed law, like one that will make trolls pay legal costs if their claims are rejected, will remove a good deal of the risk that smaller companies face when they decide to resist a spurious lawsuit," Snyder writes. That said, "You'd have to be wildly optimistic to think that software patents will be abolished. Although the EFF's proposals call for the idea to be studied, [EFF attorney Daniel] Nazer doesn't expect it to happen; he instead advocates several reforms not contained in the Innovation Act."
GNU is Not Unix

Serious Network Function Vulnerability Found In Glibc 211 211

An anonymous reader writes: A very serious security problem has been found and patched in the GNU C Library (Glibc). A heap-based buffer overflow was found in __nss_hostname_digits_dots() function, which is used by the gethostbyname() and gethostbyname2() function calls. A remote attacker able to make an application call to either of these functions could use this flaw to execute arbitrary code with the permissions of the user running the program. The vulnerability is easy to trigger as gethostbyname() can be called remotely for applications that do any kind of DNS resolving within the code. Qualys, who discovered the vulnerability (nicknamed "Ghost") during a code audit, wrote a mailing list entry with more details, including in-depth analysis and exploit vectors.
Networking

Ask Slashdot: Migrating a Router From Linux To *BSD? 403 403

An anonymous reader writes I'm in the camp that doesn't trust systemd. You can discuss the technical merits of all init solutions all you want, but if I wanted to run Windows NT I'd run Windows NT, not Linux. So I've decided to migrate my homebrew router/firewall/samba server to one of the BSDs. Question one is: which BSD? Question two: where's some good documentation regarding setting up a home router/firewall on your favorite BSD?
It's fine if the documentation is highly technical, I've written linux kernel drivers before :)

If you can't understand it, it is intuitively obvious.

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