Re: Samba/FTP slow write fast read
George, On Sat, Nov 3, 2012 at 8:56 PM, George Toft geo...@georgetoft.com wrote: Here are the cases I had: Win7 client 1 (VMware host) using Windows Explorer, read fast, write slow Win7 client 1 using FTP, read fast, write slow Win7 samba client 2 using Windows Explorer, read fast, write fast Linux client 1 using FTP, read fast, write fast Linux client 1 using smbclient, read fast, write fast As you can see, anything that had to do with writes from Win7 client 1, which was the VMware host, went slow. And this did have a large virtual drive - it was 500GB. That was probably the problem :) Also the version of SMB on the VMware host? SMB - not SMB2, right? Upgrade that Vmware to ESXi. I've since moved the client from VMware to proxmox-ve on a difference system and life is good. I won't be able to pursue this any further. Same config files and it works very well. Regards, George Toft On 11/3/2012 8:16 PM, Lisa Kachold wrote: Hi George, On Sat, Oct 27, 2012 at 6:01 PM, George Toft geo...@georgetoft.comwrote: Spent several hours researching this one - can't find a solution. I hope someone here can hit me with a clue-by-four. CentOS 6.3 64-bit virtual running under VMware 2.0.2 fresh install with FTP/Samba/NFS running. I copied 500+GB of data from the old computer to the new one using NFS at full network speed (11+ MB/sec). Life's good. Now here it is a day later, and my samba write speed is a blazing 80KB/sec (up from 40KB/s when I started troubleshooting). I read samba should approach FTP speed and I verified it does - FTP writes to the new machine at about the same speed. Reads still take place a full speed (now it's on a 1Gbps network) - 33MB/sec. Writes . . . 99.8% slower. I did not have this problem on the previous samba server (CentOS 4.8 32-bit). I added memory (it now has 1GB RAM, 1 GB swap) and it has 2 CPU's. This had no effect. In summary, NFS works at full speed both ways. Samba/FTP are fast on reads but snail slow on writes. My next thought is to install ClearOS, test it, and copy their smb.conf. Or install CentOS 5.x and see if it has the same problems. Any ideas where to look on this one? smb.conf necessary. -- Regards, George Toft Microsoft 7 uses smb 2.2, btw -- protocol step down might add to the lag? What is your smb version on each node? CIFS clients? http://www.codefx.com/CIFS_Explained.htm A given client and server may implement different sets of protocol variations which they negotiate before starting a session. There are a great many considerations for this problem: 0) Samba in VMware: http://www.vmware.com/support/ws45/doc/network_samba_ws.html 1) Active .vs Passive FTP: http://www.youtube.com/watch?v=bqrlBicM8lE 2) Disk type: Dynamically allocated VMware virtual disks are extremely slow with writes. Huge virual disks over say 300 gb are also really really slow for writes. Raid 5 or greater on VVware is also extremely slow with writes, depending on the version of VMware. 3) What kind of network are you using? By default there are three virtual networks created on a VMware server. They are: VMnet0 – Bridged VMnet1 – Host-only VMnet8 – NAT 4) Networking UDP packets for SMB: SMB uses UDP which is a connection-less protocol. In other words it simply broadcasts. UDP uses a simple communication model without implicit transmission checks for guaranteeing reliability, sequencing, or datagram integrity. Though these factors might seem to suggest that UDP is not a useful protocol, it is still widely used in particular areas where speed, more than reliability, is of utmost importance. With UDP, error checks and corrections are carried out in the communicating application, not at the network layer. However, if error checks and corrections are needed at the network layer, the application can use Transmission Control Protocol (TCP) or Stream Control Transmission Protocol (SCTP), which are specifically formulated for this reason. Since UDP does not have the overhead of checking whether the data has reached the destination every time it is sent, it makes the protocol that much faster and more efficient. UDP is often used for time sensitive applications where missing data is preferred to late arriving data. UDP packets can also create broadcast storms (NFS 3), therefore it's not suggested that SMB or older NFS3 5) Putting it all together: Using Samba for File Sharing on a Host-only Network On a Linux host computer, VMware ESX Server can automatically install and configure a Samba server to act as a file server for Microsoft Windows guest operating systems. You can then use Windows Explorer in the virtual machine to move and copy files between virtual machine and host — or between virtual machines on the same network — just as you would with files on physical computers that share a network connection. The lightly modified Samba server installed by
Re: Samba/FTP slow write fast read
samba version: samba-3.0.33-3.39.el5_8 I would love to use ESX3i, but the VI client is only good for 60 days, then I have to pay - that's why I didn't go down that road. Regards, George Toft On 11/4/2012 10:38 AM, Lisa Kachold wrote: George, On Sat, Nov 3, 2012 at 8:56 PM, George Toft geo...@georgetoft.com mailto:geo...@georgetoft.com wrote: Here are the cases I had: Win7 client 1 (VMware host) using Windows Explorer, read fast, write slow Win7 client 1 using FTP, read fast, write slow Win7 samba client 2 using Windows Explorer, read fast, write fast Linux client 1 using FTP, read fast, write fast Linux client 1 using smbclient, read fast, write fast As you can see, anything that had to do with writes from Win7 client 1, which was the VMware host, went slow. And this did have a large virtual drive - it was 500GB. That was probably the problem :) Also the version of SMB on the VMware host? SMB - not SMB2, right? Upgrade that Vmware to ESXi. I've since moved the client from VMware to proxmox-ve on a difference system and life is good. I won't be able to pursue this any further. Same config files and it works very well. Regards, George Toft On 11/3/2012 8:16 PM, Lisa Kachold wrote: Hi George, On Sat, Oct 27, 2012 at 6:01 PM, George Toft geo...@georgetoft.com mailto:geo...@georgetoft.com wrote: Spent several hours researching this one - can't find a solution. I hope someone here can hit me with a clue-by-four. CentOS 6.3 64-bit virtual running under VMware 2.0.2 fresh install with FTP/Samba/NFS running. I copied 500+GB of data from the old computer to the new one using NFS at full network speed (11+ MB/sec). Life's good. Now here it is a day later, and my samba write speed is a blazing 80KB/sec (up from 40KB/s when I started troubleshooting). I read samba should approach FTP speed and I verified it does - FTP writes to the new machine at about the same speed. Reads still take place a full speed (now it's on a 1Gbps network) - 33MB/sec. Writes . . . 99.8% slower. I did not have this problem on the previous samba server (CentOS 4.8 32-bit). I added memory (it now has 1GB RAM, 1 GB swap) and it has 2 CPU's. This had no effect. In summary, NFS works at full speed both ways. Samba/FTP are fast on reads but snail slow on writes. My next thought is to install ClearOS, test it, and copy their smb.conf. Or install CentOS 5.x and see if it has the same problems. Any ideas where to look on this one? smb.conf necessary. -- Regards, George Toft Microsoft 7 uses smb 2.2, btw -- protocol step down might add to the lag? What is your smb version on each node? CIFS clients? http://www.codefx.com/CIFS_Explained.htm A given client and server may implement different sets of protocol variations which they negotiate before starting a session. There are a great many considerations for this problem: 0) Samba in VMware: http://www.vmware.com/support/ws45/doc/network_samba_ws.html 1) Active .vs Passive FTP: http://www.youtube.com/watch?v=bqrlBicM8lE 2) Disk type: Dynamically allocated VMware virtual disks are extremely slow with writes. Huge virual disks over say 300 gb are also really really slow for writes. Raid 5 or greater on VVware is also extremely slow with writes, depending on the version of VMware. 3) What kind of network are you using? By default there are three virtual networks created on a VMware server. They are: VMnet0 -- Bridged VMnet1 -- Host-only VMnet8 -- NAT 4) Networking UDP packets for SMB: SMB uses UDP which is a connection-less protocol. In other words it simply broadcasts. UDP uses a simple communication model without implicit transmission checks for guaranteeing reliability, sequencing, or datagram integrity. Though these factors might seem to suggest that UDP is not a useful protocol, it is still widely used in particular areas where speed, more than reliability, is of utmost importance. With UDP, error checks and corrections are carried out in the communicating application, not at the network layer. However, if error checks and corrections are needed at the network layer, the application can use Transmission Control Protocol (TCP) or Stream Control Transmission Protocol (SCTP), which are specifically formulated for this reason. Since UDP does not have the overhead of checking whether the data has reached the destination every time it is sent, it makes the protocol that much faster and more efficient. UDP is often used for time sensitive applications where missing data is preferred to late arriving data. UDP packets
