Re: [SlimDevices: Touch] WLAN max. throughput ?
streumix;564720 Wrote: It looks like jive interupts in some way and slows down the file transfer. First I thought of on-demand scanning issues of the activated built-in server when storing to the USB-HDD. But scp transfers into /tmp cause similar CPU load activities of jive. Shutting down the built-in server doesn't make a difference, too. Do you get the same transfer rate both with and without the server running? Do you get the same rate using both WIFI and wired ethernet? You've given details about the CPU load, but don't say whether there's any difference in transfer speed. -- JJZolx JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
As mentioned at the beginning of the post, the transfer rate for all configurations was pretty much the same. 450..500kByte/sec. Another strange fact. -- streumix streumix's Profile: http://forums.slimdevices.com/member.php?userid=39267 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
[SlimDevices: Touch] WLAN max. throughput ?
Hi, while playing with the samba USB HDD sharing options, I've experienced pretty slow data rates. Therefore, I did measure the WLAN data throughput based on scp, too. (scp a 4MB into the ramdisk - scp 4MBdummy.bin r...@squeezeboxtouch/tmp) But all I could get (scp or SMB export) is somewhat around 500kB/sec max. (4MBit) ? Is this a typical value or is there a problem with my WLAN setup. What can I expect ? Since my router tells me all clients are running fine at 54MBit, I'd expect to come close a throughput = 20 MBit. What are your WLAN data transfer rates ? Toby -- streumix streumix's Profile: http://forums.slimdevices.com/member.php?userid=39267 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
streumix;564398 Wrote: Hi, while playing with the samba USB HDD sharing options, I've experienced pretty slow data rates. Therefore, I did measure the WLAN data throughput based on scp, too. (scp a 4MB into the ramdisk - scp 4MBdummy.bin r...@squeezeboxtouch/tmp) That's not measuring the transfer rate: it's also measuring the performance of scp and smb, as well as the file system and the external drive. ie, you're adding encryption overhead as well as disk io overhead and lumping it in as network performance. -- snarlydwarf snarlydwarf's Profile: http://forums.slimdevices.com/member.php?userid=1179 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
On 07/26/2010 09:48 AM, streumix wrote: But all I could get (scp or SMB export) is somewhat around 500kB/sec max. (4MBit) ? Is this a typical value or is there a problem with my WLAN setup. What can I expect ? Since my router tells me all clients are running fine at 54MBit, I'd expect to come close a throughput = 20 MBit. Sorry, there is a huge difference between the signaling rate and actual throughput. There is zero chance you will ever see 54mbit. That would require no contention, no overhead. SCP adds some delay with the encryption, but with modern processors, that is usually not a problem. If you can deliver data at 20% of the channel rate, be happy. Its not out of line. If there are other WiFi networks in sight, they will contend even when your are doing just one-to-one connections. I can see eight WiFi hot spots from my living room laptop. The solutions are simple: stop using WiFi and use a wired connection. Gigabit switches are cheap. Ethernet is all about collision detection and retry. That wastes a lot of bandwidth. Its not a bug, its a feature. -- Pat Farrell http://www.pfarrell.com/ ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
Now, I didn't want to start a thread about how to deinfe network throughput. I just had been astonished by the large gap between signaling bandwidth (54Mbit) and the effective transfer speed I'm getting for the two two tested methods of file transfer (SMB and scp). Of course, there's a full stack of protocol overhead (physical layer ...IPTCPscpfile transfer), but here we're talking about a 25...30% max. (worst case). Further, signal quality on a radio link level doesn't allow to specify an exact number in general, but : I have a 54MB WiFi cell with a router and a single client (SB Touch). My PC is now connected via wire (100MBit) and there are no strong interfere for the radio link accoring to the SNR numbers I can get for from my router. This means we have a half-duplex WiFi link between router and SB Touch when transfering a large files (PC and SB Touch do not share bandwidth for up- and downlink!). What I get is a net file transfer rate of 500kByte/sec (4Mbit) for both scp and SMB. Now, do we really have 90% protocol overhead, etc .. ??? 4MBit net rate is way of from typical numbers you can get for a 54Mbit physical link with TCP/IP(scp/smb) file transfer. There must be a serious limiting factor ! (SB Touch CPU ?) Since I've some doubt's regarding my router (AVM Fritz!Box 3030), I was asking for other users experience and their transfer rates. Meanwhile, I've switched my PC from WiFi to cable to double x-check. No influence. According to other forum posts (not in this forum), up to 3Mbyte/sec net SMB file transfer rate are possible between two WiFi clients in a 54MBit cell (no ad-hoc / via router,with shared bandwidth for up and downlink). Could anyone report his file transfer rate for SMB access via 54Mbit ? 500kByte is way below the typ. limits of USB storage devices (even the worst USB memeory sticks) There's no need to discuss these limits at the moments. -- streumix streumix's Profile: http://forums.slimdevices.com/member.php?userid=39267 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
On 07/26/2010 10:52 AM, streumix wrote: protocol overhead (physical layer ...IPTCPscpfile transfer), but here we're talking about a 25...30% max. (worst case). There must be a serious limiting factor ! (SB Touch CPU ?) Since I've some doubt's regarding my router (AVM Fritz!Box 3030), I was asking for other users experience and their transfer rates. No, getting 25 % is good. Getting 10% is common with other WiFi It has nothing to do with the Touch's CPU or NIC Its a feature, not a bug Sometimes you can change the WiFi channel and have fewer collisions. -- Pat Farrell http://www.pfarrell.com/ ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
What you're seeing probably has little to do with your wireless network's throughput. Data rates when transferring files to and from the Touch can be pretty dismal. The Touch is remarkably slow at just about everything it does. You won't be measuring your wifi speed by running data transfers between the Touch and another computer on your network. If you want to do that then try doing transfers between machines that you know aren't bottlenecking the transmission. You might also try transfers to and from the Touch with both ends wired to your network to get an idea of what it's capable of in ideal conditions. -- JJZolx JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
I just ran a small test on my wireless network and I get about 21-22 Mbps. This is the speed transferring some large files from my file server to a laptop. -- JJZolx JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
A couple more tests, transferring files to and from the Touch over wireless: Copying files to an SD card in the Touch I get a pretty erratic 2-7 Mbps, probably averaging around 4 Mbps. In the other direction, copying from the Touch I get a fairly steady 7-9 Mbps. -- JJZolx JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] WLAN max. throughput ?
JJZolx;564447 Wrote:
A couple more tests, transferring files to and from the Touch over
wireless: Copying files to an SD card in the Touch I get a pretty
erratic 2-7 Mbps, probably averaging around 4 Mbps. In the other
direction, copying from the Touch I get a fairly steady 7-9 Mbps.
Have you tried if a USB drive attached to the Touch is faster or slower
than the SD card ?
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Re: [SlimDevices: Touch] WLAN max. throughput ?
erland;564539 Wrote: Have you tried if a USB drive attached to the Touch is faster or slower than the SD card ? No, I haven't. The one USB drive that I own rarely ever worked with the Touch. -- JJZolx JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=80707 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
