ZFS Speeds not consistent

[Makaveli6103]

I updated from 7.2 to 8.3 and am not getting consistent speeds. At first I was getting around 50-60 MB/s but am now only getting around 16MB/s (both read). I ran autotune but no improvement and am not sure what to do to get back to my original speeds.

FreeNAS-8.3.0-RELEASE-p1-x64 (r12825)
ASUS E35M1-M PRO (1.6Ghz Dual core)
7773MB Memory
4 x 2TB Samsung F4 HD204UI SATA II
Intel NIC PWLA8391GTBLK-1PK PRO/1000 GT

I ran autotune and this is what it gave me.

Code:

net.inet.tcp.sendbuf_max 2097152
kern.ipc.maxsockbuf 2097152	
net.inet.tcp.recvbuf_max 2097152

vfs.zfs.arc_max 4128163522	
vm.kmem_size_max 5733560448
vm.kmem_size 4586848358

 

[joeschmuck]

try checking your zpool status, see if you are degraded.

 

[Makaveli6103]

try checking your zpool status, see if you are degraded.

Nope. Status is Online with no known data errors.

 

[Makaveli6103]

I changed compression to inherit on my main ZFS volume and I am back up to 30MB/s, I forgot I changed it to gzip. But still not 60.

 

[joeschmuck]

Hum... I don't use compression. Well at least your pool is in-tact. Did you have compression off when you had the 60MB/sec speed?

 

[cyberjock]

First thing I'd do is turn off compression and try copying new files to/from the server. Any files created on the server already are compressed.

Compression can tank your performance without a very fast CPU.

 

[joeschmuck]

Yes, I too was thinking the CPU in this system might not be fast enough for good performance with compression turned on which is why I asked if it was off originally, which I suspect was the case.

What kills me are the way these threads always start... It was working good and now it doesn't. No mention of many details, if any, and then you find out later that changes were made which of course likely is where the problem resides. I'm taking the weekend off. I know I don't offer as much help as I use to but it's getting old, people don't bother reading the manual or even doing a little research themselves. The search engine on these forums mighty not be fantastic but if you use Google, type in some good key words, odds are one of the forum pages will pop up. This is a general statement, not specifically directed to the OP of this thread.

 

[cyberjock]

Same. I'm on strike. This is too old to be fun anymore. The second I saw the title "ZFS speeds not consistent" I immediately thought "$1000 says compression must be on". Guess what....

 

[Makaveli6103]

Sorry guys I am new to messing around with my Freenas. On my old system I just set it up and let it be. I am trying to dig deeper this time and learn more about it. I set compression and atime to inherit on my main volume. But my question is do they default to none if it is the zpool?

 

[budmannxx]

What if we (and by "we" I mean the senior people who get to make decisions around here, not actually me) implemented a new forum rule where in order to have a question answered, you had to actually post 3 links to the google searches you did before you posted the question? I think 3 should be enough for everyone to know if the OP is being lazy or not. The people who answer all the questions around here would have some much better options, such as:

• helping people craft better google queries (bonus: this helps you in all aspects of your life, not just for FreeNAS!) or
• answering the questions if the posted searches were good but still didn't yield enough results to fix the issue or
• ignoring or just closing the thread without response when the required search links aren't posted with a question (or the links are clearly lazy attempts to bypass the new forum rule).

It would be an absolute shame if the experts here were driven away by the sheer laziness of some of the (usually) new members. In addition to the understandable sentiment in this thread from cyberjock and joeschmuck, I can see protosd getting similarly frustrated in his recent posts. Obviously everyone was new here once. But my personal opinion is that way too much patience has been extended to people who are lazy or who don't follow the forum rules (like posting your specs). I'd hate for this forum to become one of those snarky "RTFM, noob" places, but it's easy to see how that happens. It's supposed to be a two-way street between people learning for themselves and the experts giving out their advice for free.

And, yeah, I realize I'm breaking a forum rule by hijacking this thread, but when I saw these posts I got genuinely scared (even if they were a bit tongue-in-cheek):

What kills me are the way these threads always start... It was working good and now it doesn't. No mention of many details, if any, and then you find out later that changes were made which of course likely is where the problem resides. I'm taking the weekend off. I know I don't offer as much help as I use to but it's getting old, people don't bother reading the manual or even doing a little research themselves. The search engine on these forums mighty not be fantastic but if you use Google, type in some good key words, odds are one of the forum pages will pop up. This is a general statement, not specifically directed to the OP of this thread.

Same. I'm on strike. This is too old to be fun anymore. The second I saw the title "ZFS speeds not consistent" I immediately thought "$1000 says compression must be on". Guess what....

 

[jgreco]

Wouldn't work unless it was enforced by the forumware, and quite frankly, as well-meaning as the admins are, they've got a less-than-ideal track record of getting even fairly standard features to work consistently and correctly. Which is why *I've* not been posting as much lately, I have better things to do than trying to remember which things-I've-responded-to-but-the-forumware-has-held-the-post-for-a-moderator so I end up a few hours later thinking "I didn't respond to that, I should do so."

 

[jgreco]

but in all fairness it hasn't done that lately, and they seem to have reduced the "120 seconds between posts" to 30, which is a vast improvement.

 

[cyberjock]

Do you have any idea how long this fight between people that don't do their home work and the senior members have gone on? I'd say at least 5 months for some people, and more than a year for others.

But yeah, I'm just gonna leave the noob questions unanswered and let them fail. It's not like its a big deal if some people that shouldn't be using FreeNAS can't figure out how to use it anyway.

 

[budmannxx]

I just meant as a new policy that could be a sticky/announcement, not as a technical requirement for actually posting. Since I get the sense that at least some of the senior people here read almost every post, I figured they could just close the offending threads. While I totally agree with leaving these types of threads unanswered, closing them would eliminate the "bump??" followup posts that move them back to the top. If we didn't want to be so iron-fisted, maybe there could be a "Lazy" category that they get moved to. Experienced forum guys could just ignore that category, but other people could be free to talk themselves in circles to their hearts' content.

I'm just trying to throw out some ideas to keep the experts that are here, here. I've seen a bunch of "you should search first, but here's an answer or suggestion for your problem" posts. Those are very nice responses for the OP, and I wish they worked, but it doesn't seem like the group as a whole is learning its lesson. Unfortunately it's starting to look like the responses need to shift more towards "you should search first, and I'm not going to answer you." That's mean, but the nice way hasn't been working. I would trust the senior members around here to differentiate between when this "tough love" is necessary and when a more junior member has made an honest mistake.

 

[cyberjock]

Since I get the sense that at least some of the senior people here read almost every post, I figured they could just close the offending threads.

I do read every post, except for the people I have on my ignore list. Those people on my ignore list have shown their ignorance to be so severe I won't even waste my time trying to read them.

While I totally agree with leaving these types of threads unanswered, closing them would eliminate the "bump??"

Except that I closed a thread that was promptly reopened by one of the admins with the argument that "only advertisement threads should be closed" I sent him a PM and he never responded. See jgreco's comment for my feeling regarding the forum admins and their lack of supervising the forum properly.

If we didn't want to be so iron-fisted, maybe there could be a "Lazy" category that they get moved to.[/QUOTE]

I wanted a "wall of shame" where we move topics that have been covered to death to that category to show that they need to use the search feature. It's not anyone hasn't heard of "search" before.

I've seen a bunch of "you should search first, but here's an answer or suggestion for your problem" posts. Those are very nice responses for the OP, and I wish they worked, but it doesn't seem like the group as a whole is learning its lesson.

Emphasis is mine. That's the problem.

That's mean, but the nice way hasn't been working. I would trust the senior members around here to differentiate between when this "tough love" is necessary and when a more junior member has made an honest mistake.

This is exactly correct. But again, as jgreco said earlier, nobody is willing to enforce it. I have 3 presentations written that need about 15 mins each and then posted. And why haven't I posted them yet you ask? Because I'm fearful of the 50 questions that noobs are going to ask as soon as I post them, and I really don't feel like entertaining a bunch of incompetent posters that can't use search. And I don't feel that I can trust that the forum admins will lay the smack down if necessary after I post them.

 

[cyberjock]

but in all fairness it hasn't done that lately, and they seem to have reduced the "120 seconds between posts" to 30, which is a vast improvement.

I haven't noticed. I post so much less often because 2/3 of the threads I just close after I shed a tear or two because it was just asked less than 24 hours before.

 

[jgreco]

I haven't noticed. I post so much less often because 2/3 of the threads I just close after I shed a tear or two because it was just asked less than 24 hours before.

My bad habit of short, terse responses.

 

[ProtoSD]

What kills me are the way these threads always start... It was working good and now it doesn't. No mention of many details, if any, and then you find out later that changes were made which of course likely is where the problem resides. I'm taking the weekend off. I know I don't offer as much help as I use to but it's getting old, people don't bother reading the manual or even doing a little research themselves. The search engine on these forums mighty not be fantastic but if you use Google, type in some good key words, odds are one of the forum pages will pop up. This is a general statement, not specifically directed to the OP of this thread.

I stayed away from this thread til now. The OP was on a posting spree and I saw the direction they were headed and just stayed away.

 

[ProtoSD]

I just meant as a new policy that could be a sticky/announcement, not as a technical requirement for actually posting. Since I get the sense that at least some of the senior people here read almost every post, I figured they could just close the offending threads. While I totally agree with leaving these types of threads unanswered, closing them would eliminate the "bump??" followup posts that move them back to the top. If we didn't want to be so iron-fisted, maybe there could be a "Lazy" category that they get moved to. Experienced forum guys could just ignore that category, but other people could be free to talk themselves in circles to their hearts' content.

I'm just trying to throw out some ideas to keep the experts that are here, here. I've seen a bunch of "you should search first, but here's an answer or suggestion for your problem" posts. Those are very nice responses for the OP, and I wish they worked, but it doesn't seem like the group as a whole is learning its lesson. Unfortunately it's starting to look like the responses need to shift more towards "you should search first, and I'm not going to answer you." That's mean, but the nice way hasn't been working. I would trust the senior members around here to differentiate between when this "tough love" is necessary and when a more junior member has made an honest mistake.

Excellent post with many sentiments and ideas that us senior guys share.

The thing is if WE ignore a post, someone else just comes along and answers it anyway encouraging the behavior, and the "nice way" doesn't work.

Closing it is ok, but then there's just more clutter for people that search to dig through. I did do a mass close of thread that were over a year old, and another mass close of threads with no reply for 3 months. Spammers look for those to try and sneak stuff into.

Forum rules say its up to the moderators/admins to move or delete post at their descretion.

I've been "nice" lately and given offenders a 24 hour ban to review the rules and there have been a few that have been just flat out removed. If I'm *really* nice I'll send a PM.

Really, after 2.5 years here, I've seen just about every question answered and look forward to something that's actually new.

 

[gpsguy]

Sorry, I've been (someone) guilty of trying to help. Having participated on BBS's and forums for 30 years, it's second nature.

Last year, we used to be able to send folks to protosd's blog to read his excellent FAQ's. I'm one of the 20,000 that miss that resource, but I support his protest.

The thing is if WE ignore a post, someone else just comes along and answers it anyway encouraging the behavior, and the "nice way" doesn't work.

How many of these folks would read a new sticky? They won't even read the old one's, especially the part about posting their system spec's.

I just meant as a new policy that could be a sticky/announcement, ...

I read most of the new messages. It's another avenue for learning.