Ubuntu Networking :: Mdadmin RAID5 Very Slow Write Speed?
Jul 5, 2011
I am hoping someone can help me I setup a brand new ubuntu 11.04 64bit system with:-AMD Phoenom 840 (3.7GHz overclocked) 8GB DDR3 RAM.WD20EARS x 4madmin (RAID5) SetupFor some reason I cannot get the write speed above 15mb/s & I have tried modifying the cache_Stripe_size from 256 to 8192.My read speeds are great burst at 120mb/s & stable at about 60mb/s.The only other possiblility is it could be my HDs which I read causes slow writes not sure if thats true though. point me in the right direction so I can fix this issue as I don't want to move to the dark side (Windows) .
I just tried NFS for the first time after reading that it's considerably faster than SSHFS, which I currently use, but I'm experiencing slow write speeds and problems while copying files in nautilus.
I had a F14 samba server working flawlessly now for a quite time. Unexpectedly about a month ago the write speed slowed down around 64kbit/s and that's really slow. I haven't changed any configs, only updated the server. I've troubleshooted this from many angles: -It is not a network issue because sftp writes are good. -It is not a RAID1 issue because write speed from another directory (locally) are good. So basically samba is the only thing left.
Here's example from smb.conf: [MyShare] comment = My share path = /mnt/RAID_share writeable = yes browseable = yes writelist = +smbuser
Here's a snip from logs today: [2011/08/04 09:04:27.509273, 1] smbd/server.c:267(remove_child_pid) Scheduled cleanup of brl and lock database after unclean shutdown [2011/08/04 09:04:47.526336, 1] smbd/server.c:240(cleanup_timeout_fn) Cleaning up brl and lock database after unclean shutdown [2011/08/04 09:17:57.634660, 1] smbd/server.c:267(remove_child_pid) Scheduled cleanup of brl and lock database after unclean shutdown [2011/08/04 09:18:17.635196, 1] smbd/server.c:240(cleanup_timeout_fn) Cleaning up brl and lock database after unclean shutdown .....
I started a thread in the hardware section, but I've narrowed it down to being a software issue. The problem is that all USB devices are written to at about 1MB/s, and is read at equally slow speeds. After testing my computer on an older Ubuntu release (8.04 32bit), I verified it wasn't a hardware issue, because the read and write speeds were like they were supposed to be. Then, I downloaded the 32bit release of the Ubuntu version I'm currently using (an up-to-date version of Natty) and booted the live cd of it. It was equally slow there as well.
The read/write speeds are equally poor on openSUSE and Arch Linux, so I don't think that it's an issue with Ubuntu, as much as it seems like a kernel issue (or maybe not, you guys can correct me if it seems like it isn't ).
I have recently migrated my file server over to a HP Microserver. The server has two 1TB disks, in a software RAID-1 array, using MDADM. When I migrated simply moved the mirrored disks over, from the old server Ubuntu 9.10 (server) to the new one 10.04.1 (server).I Have recently noticed that write speed to the RAID array is *VERY* slow. In the order of 1-2MB/s order of magnitude (more info below). Now obviously this is not optimal performance to say the least. I have checked a few things, CPU utilisation is not abnormal (<5%) nor is memory / swap. When I took a disk out and rebuilt the array, with only one disk (tried both) performance was as to be expected (write speed >~70MB/s) The read speed seems to be unaffected however!
I'm tempted to think that there is something funny going on with the storage subsystem, as copying from the single disk to the array is slower than creating a file from /dev/zero to the array using DD..Either way I can't try the array in another computer right now, so I though I was ask to see if people have seen anything like this!At the moment I'm not sure if it is something strange to do with having simply chucked the mirrored array into the new server, perhaps a different version of MDADM? I'm wondering if it's worth backing up and starting from scratch! Anyhow this has really got me scratching my head, and its a bit of a pain! Any help here would be awesome, e-cookies at the ready! Cheers
I got a new machine with GA-p55A-ud3 mobo and a WDC WD10EARS 1T disk. When I tried to benchmark the disk IO, I was suprised by the low write speed:
[Children see throughput for 1 initial writers = 35962.63 KB/sec Parent sees throughput for 1 initial writers = 35962.63 KB/sec Min throughput per process = 35962.63 KB/sec
I am new to Centos and linux in general. I have just got myself a Dell 1950 server with 2x 1T SATA2 hard disks in it. now the server comes with a PERC5i Raid card with 512Mb. Well I put these in raid 0 and the raid card initilzed the disks to 128 writeback and read ahead. When I loaded centos it did not recognize the dell layout so therefore wanted to initalize it again, so I done this as it wanted. Now I created a 80gb boot and o/s partition and a 100gb swap the rest was created into LVM space to run solus vmwear. But I found the raid 0 to be getting extreamly slow read and write speeds.
Example same disks Desktop PC max 214mb/s windows vista 64 Server with centos 104mb/s
Now I am not sure but I am told that I need to align the o/s with the raid card settings but I have no idea how to do this. How to do this in plain easy step by step instructions. I mean how to calculate it, how to format the disk this way, and what files to edit where if needed. I have spent hours trying to figure out why my raid 0 is slower than a single disk.
When using launchpad and the ubuntu daily build website it is very slow. I get 1.2mb/s normally and the speed drops quickly to 0kb/s This is the case from any version of ubuntu that is installed on my laptop.In windows it is no problem, equally there is no problem from a live cd or an install on my external hard disk. Is canonical blacklisting/slow listing my ip?
I am behind a university network but am sure this problem occurs at home .I did a clean install and had no problem until about an hour ago. When I tried to re download a project using bzr my speed instantly ropped.I had downloaded it fine a couple of hours ago. I hope that someone can shine some light on this, its very hard to work on projects if I can't download them.
I have very suboptimal Internet speed in Wifi with Ubuntu. Normally in WIndows 7 I get download speeds up to 800 KB/s and a very fast Wifi experience, but in Ubuntu I get 100KB/s maximum and web page load speed is very extremely slow. Also, pinging to AP often gives very high response times and a lot of lost packages while in Windows they are very low and none packages are lost. I have a Netgear wg111v3 which worked out of box when I installed Ubuntu but always with this problem. It is updated and I've reinstalled Ubuntu many times..
Also I forgot to say that in Ubuntu the connection goes down very often and sometimes will not connect again until I reboot. Again in Windows never happened that. Motherboard: GA-MA74GM-S2H CPU: AMD Athlon 64X2 dual core 2 GB RAM Ubuntu 10.10 64 bit Wireless adapter Netgear wg111v3 USB .....
I've been using Ubuntu 8.04 for about a year and the wireless has been fine but now it's gone screwy and I can't figure out why. This has happened on my laptop and wife's who uses Ubuntu Hardy also. The speed drops to almost 0 mb/s whenever the signal strength is less than 95%.
It isn't the internet connection as vista (I dual boot) works fine below 95% signal strength. To get the internet speed to be at a level that can load an internet page, I have to within 3 feet of the router!! Both of the laptops don't use ndiswrapper, the internet connected straight away from a fresh install.
I'm experiencing slow speed transfer between two wireless connected laptops running ubuntu 9.10. Using SSH to tranfer files between these two laptops, which connect to the internet via a wirelesss router, with good speed. This is why I'm surprised by this low speed : 52.3 KB/s, averaging 3 hours and 31 minutes for a 700 Mb movie. Is there any way to make this faster ?
We have a server and we have instales an Open suse 10.3 on it. We created a Samba server also. Made to share folder, that we acces from network from other computers that have xp.
The problem is if we try to copy from server it is very slow only 100-300kb/s. The strange thing is that if i copy 1 file then its slow but if i start to copy another one the speed gos up to 10-15mb/s. Evry time i want to copy somethin or install from that server i need to start another copy. If i copy from a comp to that server the speed is normal only if i copy from server its slow.
I replaced only my mainbord and cpu and Ubuntu 9.10 boot just fine. The only issue that I have is that my connection speed dropped from 10Mb to 3Mb. I try the connection on my laptop and it is fine 10Mb, so the problem is with the PC. What else to try before reinstall Ubuntu as a final step?
I'm running Kubuntu 10.4, and I'm having a really slow Internet connection, with Windows everything works fine.
When I upload a file to an internal Ubuntu server the speed is ok ~15MB/s.
The problem is only with Internet Firefox / synaptic, any program using Internet. Last download done with synaptic display 18KB/s when normally it should be 500.
In mi fstab file I mount a smb file server at boot. The code is: //<ip address>/data /home/eng-2/NAS smbfs credentials=/home/eng-2/.smbcredentials,dir_mode=0775,gid=1000,uid=1000 0 0 Transfer rate to the server is approx 100 KB/s Whilst transfer rate from the server 16 MB/s If I mount it from Places>connect to server. Both to and from speeds are 16 MB/s. Why is it so slow when mounted through fstab?
So i am very new to linux based OS. Just started getting used to the terminal. but my problem is i am trying to install a game on steam and it is downloading very slow. i am used to getting close to 700 kb/s on windows 7 but on ubuntu 11.04 i am only getting 170-180 max. now i have searched all over and tried to fix it on my own but i just cant figure it out and am getting very frustrated. so if anybody has an idea as to how to fix this it would be greatly appreciated. (have looked through the forum by the way but as i said im new to linux and im not actually sure if im looking at the right things) but im using a wired connection. it says im connected to something called auto etho. and there is something called a loopback connection or something like that.
I'm running 11.04. I have brought a new WiFi adapter, ralink rt2070. When I browse the internet, it takes a long time to load a webpage. When I download updates, it goes at 3,060 BYTES a second. Is there any solution? I'm using the default rt2800usb driver.
I am experiencing very slow speed with the Intel 5300AGN on a Dell Studio XPS notebook and the iwlagn driver. I'm using Fedora 12 with all the latest updates available. When connecting to a G network with WPA2 security, everything goes fine at "normal" speed. When connecting to a N network with WPA2 security, the download speed falls between 0 k/s and 20 k/s max. The connection speed (as stated by Network Manager and iwconfig) is between 0 kb/s (?) and 11 Mb/s during the same session. I'm can't connect through ssh or download with scp (stalled). Web pages take a lot of time to render.
When connecting to the same N network on Window 7, everything runs fine enough. Every N network I try is the same story. Works fine on windows, badly on F12..
I have problems with my network speed when i ping my proxy server I end up getting a high packet loss generally more than 30%.I have tried to use various network monitoring softwares like etherape, wireshark, tcpdump but I am not able to get to the bottom of the problem.basically I am trying to find out where the lost packets are going.
A lot of people have the problem to find themselves with Lucid Lynx 10.04 and experience massive issues when connecting to wireless - me too. As a service, here some relevant links which promise relief:
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I tried all of them, and none reliably worked. Every solution which required re-association wtih the AP helped for some time, but nothing helped for long. First, don't let yourself fool by the disable IPv6 trap - while it is "enabled" it is acutally not used by Lucid! I have a clean install of Kubuntu 10.04 on an AMD64 Laptop with Broadcom STA driver: 03:00.0 Network controller: Broadcom Corporation BCM4328 802.11a/b/g/n (rev 03) However I can reliably stabilize my connection for some time either by manually disabling WiFi with the hardware switch or disabling WiFi by software means and re-activating. This brings speed at par with Kubuntu 9.10 until some time. Can anybody confirm this behaviour?
1 - I got the array up and running on three Seagate 1.5TB HDDs, filled it up in 6 months (mostly by putting all of my stuff in one place)
2 - Unknowingly, I bought a WD15EARS HDD, partitioned it as I would any normal drive and asked mdadm to grow my array over to the new partition
3 - Worried by abysmal read/write speed, I investigated, found out how to deal with the new HDD ( here or here )
4 - Being a newbie at this, I opted to do a trial run before wiping the disk and unmount/mount the partitions, LVM layers, SW RAID array. This is there I messed up.
When i try to copy files from my samba server (Ubuntu 9.10) to my windows seven media center, the speed is extremely slow. So slow that is better to download 100mb file from the internet, than from my lan. And on my lan, every card and switch is at 1000 mbps speeds on cat5 cables. And from XP or other linux machine
I am getting extremely poor write speeds with my RAID. My setup is as follows: > HP Proliant Microserver > 4 2TB Samsung F4 drives > 60GB root drive > Ubuntu 10.10 64bit > mdadm 3.2.2. I have two of the above servers, connected via gigabit LAN. The read speeds I am happy with, but write speeds are running at about 20Mb/s at the very best, Especially when people with a similar setup on a machine like this are running at about 90MB/s write speeds. My array is as follows (mdadm --detail -D /dev/md0):
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I have also started the partitions at 64 instead of 63 in a bid to correctly align the partitions, although this doesn't seem to have made any difference.
I have ubuntu server 10.04 on a server with 2.8ghz 1gb ddr2 with the os on a 2gb cf card attached to the IDE channel and a software raid5 with 4 x 750gb drives. On a samba share using these drives I am only getting around 5 MB/s connected via wireless N at 216mbps and my router and server both having gigabit ports. Is a raid 5 supposed to be that slow? I was seeing speeds of anywhere from 20-50MB/s from other people and am just wondering what i am doing wrong to be so far below that.
Here is my brief hardware and software detail in my production environment : AMD Phenom X4 3.4gHZ (Over clock to 4gHZ, 8G of Memory, 1TB 7200rpm Harddrive, Running Ubuntu server 10.10.My web production environment were pieced together 3 weeks ago.Here is my dilemma. started out with less that 40 users and now hitting 4,000 unique users per day.Now I am thinking I need faster write to disk and backup of data so I am thinking about putting together a Raid5.
I preparation for this.I have bought a new motherboard, AMD Phenom X4 3.6, and 2 more 2TB 7200rpm (Currently, I have a 2TB 7200rpm not used much)Been digging around this forum for posts with raid setup but still not sure how to seamlessly moving the some 10Gig of data from my current running prod environment once I have RAID5 installed on this new machine via the LIVE Ubuntu Server CD.
I have the following nasty issue:I am using fedora 12 and I use vpn for working remote.When I browse the internet the speed is very slow!even when I do a yum update it downloads the packages with max 100kb. if I drop the vpn connection I download the packages with 1Mbdo you know what the problem could be? i created the vpn connection using the network manager...it is a regular pptp connection for the vpn!
I'm running ubuntu 9.10, and created a softraid5 with no problems. Now i need it to automount with user read/write access, and i need to make some network share folders. My fstab has the following line for the raid:
Code: /dev/md0 /media/raid auto rw,user,auto,exec 0 0 After i mounted it, i changed the permission with:
Code: sudo chmod 777 /media/raid/ So now i can create folders and files on it. Then i created some shares, one with guest access and other with no guest access.
Now the questions:
1) If i access the guest shared folder via WinXP, i create files and folders, but they appear locked on ubuntu, so i cant access them until i change the permissions. If i go to proprieties/Permissions, the owner is "nobody".
2) What password do i need to use on WinXP, and i try to access the non-guest shared folded? Do i need to create a user just for that?
When writing to the drive the max speed I get is 5 megabytes per second. I Googled it and tried some other posted Fstab lines but all disabled my write access for some reason even without "RO" in the line. Can someone please give me some guidance as to how I get the normal Sata HD transfer speed which is more like 55-75 megs or more per second or so?
I am running Ubuntu 10.04 from a USB key (16GB). Overall I'm pretty fine with it but there are a few problems I am having. It seems to be very slow. In particular, Firefox and Pidgin freeze every now and then, before becoming active again. The same thing also happens for other applications such as Rhythmbox, Gedit, and the terminal. Additionally my start up and shut down times are horrible (worse than when I use Vista and Ubuntu 8.04). I was wondering if there is something with my install or if this is all due to the fact that I am running from a USB. I don't think it's the USB since I ran 8.04 from a USB HDD (55GB) and didn't have any problems with speed.
