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Groups > comp.sys.raspberry-pi > #25726 > unrolled thread
| Started by | nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) |
|---|---|
| First post | 2021-01-10 17:46 +1300 |
| Last post | 2021-01-11 15:39 +0000 |
| Articles | 20 on this page of 66 — 14 participants |
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My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-10 17:46 +1300
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-11 04:10 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-12 00:28 +1300
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-12 10:26 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-12 10:57 +0000
Re: My darn NAS... Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2021-01-12 12:16 -0500
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-12 18:04 +0000
Re: My darn NAS... Ahem A Rivet's Shot <steveo@eircom.net> - 2021-01-12 18:38 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-13 12:20 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-13 12:42 +0000
Re: My darn NAS... Ahem A Rivet's Shot <steveo@eircom.net> - 2021-01-13 12:39 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-13 14:23 +0000
Re: My darn NAS... Ahem A Rivet's Shot <steveo@eircom.net> - 2021-01-13 18:21 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-13 19:25 +0000
Re: My darn NAS... Daniel James <daniel@me.invalid> - 2021-01-14 12:58 +0000
Re: My darn NAS... TimS <timstreater@greenbee.net> - 2021-01-14 13:10 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 13:35 +0000
Re: My darn NAS... Scott Alfter <scott@alfter.diespammersdie.us> - 2021-01-13 17:33 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-13 16:22 +1300
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-12 13:20 +1300
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-13 09:46 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-13 12:21 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-13 16:20 +1300
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 08:56 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 11:06 +0000
Re: My darn NAS... TimS <timstreater@greenbee.net> - 2021-01-14 11:43 +0000
Re: My darn NAS... Ahem A Rivet's Shot <steveo@eircom.net> - 2021-01-14 12:22 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 12:43 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 13:29 +0000
Re: My darn NAS... druck <news@druck.org.uk> - 2021-01-14 17:42 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 12:36 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 13:22 +0000
Re: My darn NAS... nospam.Richard.Falken@f1.n770.z6840.fidonet.org (Richard Falken) - 2021-01-14 11:45 +1300
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 18:05 +0000
Re: My darn NAS... TimS <timstreater@greenbee.net> - 2021-01-14 18:29 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 18:35 +0000
Re: My darn NAS... TimS <timstreater@greenbee.net> - 2021-01-15 11:25 +0000
Re: My darn NAS... nospam.Richard.Falken@f1.n770.z6810.fidonet.org (Richard Falken) - 2021-01-14 06:36 +1300
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 12:53 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 13:19 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 14:29 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 14:52 +0000
Re: My darn NAS... druck <news@druck.org.uk> - 2021-01-14 17:31 +0000
Re: My darn NAS... Martin Gregorie <martin@mydomain.invalid> - 2021-01-14 13:24 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-14 13:39 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 14:07 +0000
Re: My darn NAS... Martin Gregorie <martin@mydomain.invalid> - 2021-01-14 15:22 +0000
Re: My darn NAS... Scott Alfter <scott@alfter.diespammersdie.us> - 2021-01-14 20:08 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-15 08:34 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-14 13:17 +0000
Re: My darn NAS... Pancho <Pancho.Dontmaileme@outlook.com> - 2021-01-16 12:30 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-18 17:57 +1300
Re: My darn NAS... Martin Gregorie <martin@mydomain.invalid> - 2021-01-19 13:37 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-21 18:06 +1300
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-11 10:15 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-11 15:16 +0000
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-11 15:31 +0000
Re: My darn NAS... Chris Green <cl@isbd.net> - 2021-01-11 18:05 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-12 00:31 +1300
Re: My darn NAS... Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2021-01-12 12:19 -0500
Re: My darn NAS... The Natural Philosopher <tnp@invalid.invalid> - 2021-01-13 12:09 +0000
Re: My darn NAS... druck <news@druck.org.uk> - 2021-01-11 10:25 +0000
Re: My darn NAS... nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) - 2021-01-12 00:35 +1300
Re: My darn NAS... Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2021-01-12 12:25 -0500
Re: My darn NAS... druck <news@druck.org.uk> - 2021-01-12 19:32 +0000
Re: My darn NAS... "NY" <me@privacy.invalid> - 2021-01-11 15:39 +0000
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| From | nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) |
|---|---|
| Date | 2021-01-10 17:46 +1300 |
| Subject | My darn NAS... |
| Message-ID | <497943163@f420.n105.z1.binkp.net> |
I had setup an Open Media Vault on a Raspberry Pi 3, which I know doesn't have gigabit ethernet... I use cheap USB Hard Drives, 2 x 4TB Seagates... I run a PLEX server and, although I'm sure I don't have awesome 4k content [Probably not even all 1080p!], it seems to work just fine for streaming to ONE television at a time. However, both on my Samba Shares and NFS Shares, I'm getting around 10mb/Sec transfer rates. Sometimes they'll bump up to +/-18mb but not often; I'm sure this is just the particular instance reporting wrong.... I'm around 10-12mb constantly. So... I thought my bottle-neck was the Pi, and not having gigabit - I threw a Pi 4 8gbRAM model at it today... I reinstalled fully, and setup from scratch. I've only pushed over one of my drives YET because... wouldn't ya know it, the transfer rate is the EXACT same as on the Pi 3!! I did some dd and hdparm commands: 'dd if=/dev/zero of=/tmp/test1.img bs=1G count=1 oflag=dsync' @ 184 MB/s 'dd if=/dev/zero of=/tmp/test2.img bs=512 count=1000 oflag=dsync' @ 27.5 MB/s (Which, I don't even get if I tested the right drive becaues the HDD is @ /sda1 / /sda 'hdparm -t /dev/sda1' @178 MB/sec @180 MB/sec @177 MB/sec (hdparm gave an error of SG_IO: bad/missing sense data, sb[]: 70 00 05 00 00 00 00 0a 00 00 00 00 00 24 00 00 00 00 00 00 00 00 00 00 00 00), which I didn't understand but... So I *think* my HD is reading at 180MB-ish and writing at 28MB??? Where is my bottle-neck? I *thought* with a gigabit connection I could get over 100MB/s on a shared folder transfer over my network. I am doing this WiFi to my ThinkPad laptop - hmmmm... maybe this old ThinkPad has a sucky WiFi card? Maybe I should plug the laptop into ethernet and see what the transfer rates are then??? 'Lost in NAS-land, pretty decent for a newbie but... where's the beef?' |07p|15AULIE|1142|07o |08.........
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-11 04:10 +0000 |
| Message-ID | <rtgj4d$l86$1@dont-email.me> |
| In reply to | #25726 |
On 10/01/2021 04:46, paul lee wrote: > Where is my bottle-neck? I*thought* with a gigabit connection I could get over > 100MB/s on a shared folder transfer over my network. I am doing this WiFi to my > ThinkPad laptop - hmmmm... maybe this old ThinkPad has a sucky WiFi card? Maybe > I should plug the laptop into ethernet and see what the transfer rates are > then??? you said gigabit Ethernet and now you are saying Wifi? Wifi is to put it bluntly, utter shit designed for morons. Especially on laptops with no proper antennae. I have NEVER gotten more than 10Mbps *actual transfer rate* out of a basic 2.4Ghz wifi link, even feet away from the router. Even when it said it was connected at 65Mbps or 72Mbps. Remember wifi is half duplex., Every time you send an ack back, it stops the forward channel. And if any other device is on the wlan, you are sharing the link speed with that, too. It is worse than old coaxial Ethernet was at 10Mbps. It is to put it bluntly consumer crap for morons. Like StupidPhones™. Using iwconfig I have watched connection rates and attenuation vary by 3:1 for no apparent reason whatsoever. Or simply stop working altogether until reconnected. Yes, I have foil in all my walls and that makes for a tricky wifi environment, but even so. -- “The urge to save humanity is almost always only a false face for the urge to rule it.” – H. L. Mencken
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| From | nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) |
|---|---|
| Date | 2021-01-12 00:28 +1300 |
| Message-ID | <1159623022@f420.n105.z1.binkp.net> |
| In reply to | #25732 |
TN> you said gigabit Ethernet and now you are saying Wifi? TN> TN> Wifi is to put it bluntly, utter shit designed for morons. Especially on TN> laptops with no proper antennae. TN> TN> I have NEVER gotten more than 10Mbps *actual transfer rate* out of a TN> basic 2.4Ghz wifi link, even feet away from the router. Even when it TN> said it was connected at 65Mbps or 72Mbps. TN> TN> Remember wifi is half duplex., Every time you send an ack back, it stops TN> the forward channel. TN> TN> And if any other device is on the wlan, you are sharing the link speed TN> with that, too. TN> TN> It is worse than old coaxial Ethernet was at 10Mbps. It is to put it TN> bluntly consumer crap for morons. Like StupidPhones™. TN> TN> TN> Using iwconfig I have watched connection rates and attenuation vary by TN> 3:1 for no apparent reason whatsoever. Or simply stop working altogether TN> until reconnected. Yes, I have foil in all my walls and that makes for a TN> tricky wifi environment, but even so. TN> Ok... I do appreciate this reply. :P Thanks. So, yes... my daily driver machine is an older T430S Thinkpad laptop, probably with a less than current WiFi chip/card... however, I was running my NAS on a Pi 3; and just upgraded (actually still running both) to a Pi 4. My LAN/ethernet network is all gigabit+ hardware. So, what I think I should do is simply plug my Thinkpad into the ethernet port and retest both the Pi 3 and the Pi 4 NAS systems and see what I get then. I, being a fairly versed an knowledgable NEWBIE, didn't release I should be 'happy' with 12-14mb over my laptops WiFi (which again, is probably less than current since the laptops I run are from 2012). I'll connect over ethernet to both the Pi NAS systems and post again with the results, but... is this a fair and valid test that I should persue? I thought I would get better speeds OVER that WiFi connection I'm speaking of, but... understand what you've stated here. :P I am, as you can tell, still learning.. THANK YOU. |07p|15AULIE|1142|07o |08.........
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-12 10:26 +0000 |
| Message-ID | <rtjtgd$6va$1@dont-email.me> |
| In reply to | #25771 |
On 11/01/2021 11:28, paul lee wrote: > I'll connect over ethernet to both the Pi NAS systems and post again with the > results, but... is this a fair and valid test that I should persue? Absolutely -- Socialism is the philosophy of failure, the creed of ignorance and the gospel of envy. Its inherent virtue is the equal sharing of misery. Winston Churchill
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| From | Chris Green <cl@isbd.net> |
|---|---|
| Date | 2021-01-12 10:57 +0000 |
| Message-ID | <0tb0dh-7ff01.ln1@esprimo.zbmc.eu> |
| In reply to | #25771 |
paul lee <nospam.paul.lee@f420.n105.z1.binkp.net> wrote: > > So, yes... my daily driver machine is an older T430S Thinkpad laptop, probably > with a less than current WiFi chip/card... however, I was running my NAS on a > Pi 3; and just upgraded (actually still running both) to a Pi 4. My > LAN/ethernet network is all gigabit+ hardware. > I had a T430 that died (very unusual for Lenovo T series), I now have a T470 I bought used off eBay for rather less than I expected, lovely! > So, what I think I should do is simply plug my Thinkpad into the ethernet port > and retest both the Pi 3 and the Pi 4 NAS systems and see what I get then. I, > being a fairly versed an knowledgable NEWBIE, didn't release I should be > 'happy' with 12-14mb over my laptops WiFi (which again, is probably less than > current since the laptops I run are from 2012). > > I'll connect over ethernet to both the Pi NAS systems and post again with the > results, but... is this a fair and valid test that I should persue? > > I thought I would get better speeds OVER that WiFi connection I'm speaking of, > but... understand what you've stated here. :P I am, as you can tell, still > learning.. > My WiFi connection reports that it is 300Mb/s but the real speed is never anything like that. Here are my results sending from T470 laptop (WiFi connection, reports as 300Mb/s) to desktop:- bone-debian-9.4-console-armhf-2018-07-08-1gb.img 100% 850MB 16.2MB/s 00:52 So I get about half the 'expected' speed, also quite similar to your speeds I think. -- Chris Green ·
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| From | Dennis Lee Bieber <wlfraed@ix.netcom.com> |
|---|---|
| Date | 2021-01-12 12:16 -0500 |
| Message-ID | <d1mrvfl36k0i91m6envjsoelks6nnllam5@4ax.com> |
| In reply to | #25777 |
On Tue, 12 Jan 2021 10:57:04 +0000, Chris Green <cl@isbd.net> declaimed the following: > >bone-debian-9.4-console-armhf-2018-07-08-1gb.img 100% 850MB 16.2MB/s 00:52 > >So I get about half the 'expected' speed, also quite similar to your >speeds I think. Are you taking into account the IP header size, the TCP (or UDP) header size, and MTU size? The latter will tend to determine how many packets need to be sent (and for TCP, ACKed). Also, does your transfer method apply any sort of CRC or ECC logic, which will also consume some space in those packets? https://networkengineering.stackexchange.com/questions/19976/trying-to-find-out-exact-tcp-overhead-cost -- Wulfraed Dennis Lee Bieber AF6VN wlfraed@ix.netcom.com http://wlfraed.microdiversity.freeddns.org/
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| From | Chris Green <cl@isbd.net> |
|---|---|
| Date | 2021-01-12 18:04 +0000 |
| Message-ID | <3v41dh-u2221.ln1@esprimo.zbmc.eu> |
| In reply to | #25789 |
Dennis Lee Bieber <wlfraed@ix.netcom.com> wrote: > On Tue, 12 Jan 2021 10:57:04 +0000, Chris Green <cl@isbd.net> declaimed the > following: > > > > > >bone-debian-9.4-console-armhf-2018-07-08-1gb.img 100% 850MB 16.2MB/s 00:52 > > > >So I get about half the 'expected' speed, also quite similar to your > >speeds I think. > > Are you taking into account the IP header size, the TCP (or UDP) header > size, and MTU size? The latter will tend to determine how many packets need > to be sent (and for TCP, ACKed). Also, does your transfer method apply any > sort of CRC or ECC logic, which will also consume some space in those > packets? > > https://networkengineering.stackexchange.com/questions/19976/trying-to-find-out-exact-tcp-overhead-cost > When I copy from laptop to desktop (both quite fast machines with fast disks) I get something quite a bit over 100MB/s on wired Gigabit connections. So the overhead isn't that great given that the theoretical maximum would be 1000/8 which is 125MB/s. So on a 300Mb/s wireless link between the same two machines one would, sort of, expect something a bit more than 30MB/s whereas in reality one gets about half of that. -- Chris Green ·
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| From | Ahem A Rivet's Shot <steveo@eircom.net> |
|---|---|
| Date | 2021-01-12 18:38 +0000 |
| Message-ID | <20210112183854.c6ce4b8b176cdeff548ed523@eircom.net> |
| In reply to | #25792 |
On Tue, 12 Jan 2021 18:04:51 +0000 Chris Green <cl@isbd.net> wrote: > o on a 300Mb/s > wireless link between the same two machines one would, sort of, expect > something a bit more than 30MB/s whereas in reality one gets about > half of that. Which starts to make more sense when you realise the link is essentially half-duplex and subject to noise induced retries. -- Steve O'Hara-Smith | Directable Mirror Arrays C:\>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-13 12:20 +0000 |
| Message-ID | <rtmoi1$ofa$1@dont-email.me> |
| In reply to | #25792 |
On 12/01/2021 18:04, Chris Green wrote: > When I copy from laptop to desktop (both quite fast machines with fast > disks) I get something quite a bit over 100MB/s on wired Gigabit > connections. So the overhead isn't that great given that the > theoretical maximum would be 1000/8 which is 125MB/s. So on a 300Mb/s > wireless link between the same two machines one would, sort of, expect > something a bit more than 30MB/s whereas in reality one gets about > half of that. in general I have found that on a good link, speeds of a little over 1/10th Mbps rate to be obtained at the byte level, So overheads is not that heavy a penalty. Probably ~10% That's on a *full duplex* link. Broadband is full duplex. Ethernet of the cat 5 sort is full duplex. Wifi is NOT full duplex. That means that any ACK packets going back share bandwidth with the forward data stream, In a fairly nasty 'wait till the stream packet size is exceeded, then send an ack oh dear collisions/backoffs/try again...' sort of way. When my Pi zero link was going titsup before I slapped in an access point 5 feet away, although it *said* it was connected at 5Mbps, it couldn't support a 128kbps stream of audio. My so called 72Mbps links couldn't handle HD TV, which is around 5Mbps I think, reliably. I now have an Ethernet cable to where the laptop lives -- The theory of Communism may be summed up in one sentence: Abolish all private property. Karl Marx
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| From | Chris Green <cl@isbd.net> |
|---|---|
| Date | 2021-01-13 12:42 +0000 |
| Message-ID | <1f63dh-ppb61.ln1@esprimo.zbmc.eu> |
| In reply to | #25821 |
The Natural Philosopher <tnp@invalid.invalid> wrote: > On 12/01/2021 18:04, Chris Green wrote: > > When I copy from laptop to desktop (both quite fast machines with fast > > disks) I get something quite a bit over 100MB/s on wired Gigabit > > connections. So the overhead isn't that great given that the > > theoretical maximum would be 1000/8 which is 125MB/s. So on a 300Mb/s > > wireless link between the same two machines one would, sort of, expect > > something a bit more than 30MB/s whereas in reality one gets about > > half of that. > > in general I have found that on a good link, speeds of a little over > 1/10th Mbps rate to be obtained at the byte level, So overheads is not > that heavy a penalty. > > Probably ~10% Yes, that's exactly what I was trying to say really, on a wired connection one gets something over the 1/10 the Mbp/s in MBp/s. > That's on a *full duplex* link. Broadband is full duplex. Ethernet of > the cat 5 sort is full duplex. > > Wifi is NOT full duplex. > > That means that any ACK packets going back share bandwidth with the > forward data stream, In a fairly nasty 'wait till the stream packet size > is exceeded, then send an ack oh dear collisions/backoffs/try again...' > sort of way. > Simply having to interleave the ACKs with the data going in the other direction will slow things down considerably. > When my Pi zero link was going titsup before I slapped in an access > point 5 feet away, although it *said* it was connected at 5Mbps, it > couldn't support a 128kbps stream of audio. > My so called 72Mbps links couldn't handle HD TV, which is around 5Mbps I > think, reliably. > I use WiFi for as little as I possibly can. About the only major use is using my laptop interactively like now, replying to usenet posts and such. -- Chris Green ·
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| From | Ahem A Rivet's Shot <steveo@eircom.net> |
|---|---|
| Date | 2021-01-13 12:39 +0000 |
| Message-ID | <20210113123943.ec622ecbc4c0c29aabdb0df4@eircom.net> |
| In reply to | #25821 |
On Wed, 13 Jan 2021 12:20:16 +0000 The Natural Philosopher <tnp@invalid.invalid> wrote: > That means that any ACK packets going back share bandwidth with the > forward data stream, In a fairly nasty 'wait till the stream packet size > is exceeded, then send an ack oh dear collisions/backoffs/try again...' > sort of way. Your mission, should you choose to accept it, is to devise a better approach that allows full duplex wifi. As always, should you or any of your IM Force be caught or killed, the Secretary will disavow any knowledge of your actions. This post will self-destruct in five seconds. -- Steve O'Hara-Smith | Directable Mirror Arrays C:\>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-13 14:23 +0000 |
| Message-ID | <rtmvom$a6g$1@dont-email.me> |
| In reply to | #25827 |
On 13/01/2021 12:39, Ahem A Rivet's Shot wrote: > On Wed, 13 Jan 2021 12:20:16 +0000 > The Natural Philosopher <tnp@invalid.invalid> wrote: > >> That means that any ACK packets going back share bandwidth with the >> forward data stream, In a fairly nasty 'wait till the stream packet size >> is exceeded, then send an ack oh dear collisions/backoffs/try again...' >> sort of way. > > Your mission, should you choose to accept it, is to devise a better > approach that allows full duplex wifi. As always, should you or any of your > IM Force be caught or killed, the Secretary will disavow any knowledge of > your actions. This post will self-destruct in five seconds. > Shannon tells you its a hiding to nothing. If you use say two frequency bands, you would get better performance just adding them together and using collision detection. The radio spectrum is limited and precious. Go up to light frequencies and there's lots more speed available. But that doesn't punch through solid walls.. The best bet is to put a wifi point in every room, and feed them all via cable, and manage them so that StupidDevices™ are only allowed to log on to the nearest one -- Religion is regarded by the common people as true, by the wise as foolish, and by the rulers as useful. (Seneca the Younger, 65 AD)
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| From | Ahem A Rivet's Shot <steveo@eircom.net> |
|---|---|
| Date | 2021-01-13 18:21 +0000 |
| Message-ID | <20210113182113.5abc8464b59aee1ec444050a@eircom.net> |
| In reply to | #25840 |
On Wed, 13 Jan 2021 14:23:18 +0000 The Natural Philosopher <tnp@invalid.invalid> wrote: > The radio spectrum is limited and precious. Go up to light frequencies > and there's lots more speed available. But that doesn't punch through > solid walls.. Ah we have the solution - modulated X-Rays. -- Steve O'Hara-Smith | Directable Mirror Arrays C:\>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-13 19:25 +0000 |
| Message-ID | <rtnhf6$gjc$1@dont-email.me> |
| In reply to | #25849 |
On 13/01/2021 18:21, Ahem A Rivet's Shot wrote: > On Wed, 13 Jan 2021 14:23:18 +0000 > The Natural Philosopher <tnp@invalid.invalid> wrote: > >> The radio spectrum is limited and precious. Go up to light frequencies >> and there's lots more speed available. But that doesn't punch through >> solid walls.. > > Ah we have the solution - modulated X-Rays. > well you may well laugh...why stop there. Gamma rays? -- "What do you think about Gay Marriage?" "I don't." "Don't what?" "Think about Gay Marriage."
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| From | Daniel James <daniel@me.invalid> |
|---|---|
| Date | 2021-01-14 12:58 +0000 |
| Message-ID | <VA.00000d96.00466666@me.invalid> |
| In reply to | #25855 |
In article <rtnhf6$gjc$1@dont-email.me>, The Natural Philosopher wrote: >> Ah we have the solution - modulated X-Rays. > > well you may well laugh...why stop there. Gamma rays? You do know that X-Rays and Gamma rays are essentially the same thing? They occupy much the same part of the EM spectrum. The distinction often made between them is to do with their means of production. Gamma rays are produced inside the atomic nucleus while X-Rays are created by relaxation of highly excited electrons outside the nucleus. https://en.wikipedia.org/wiki/X-ray#Gamma_rays -- Cheers, Daniel.
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| From | TimS <timstreater@greenbee.net> |
|---|---|
| Date | 2021-01-14 13:10 +0000 |
| Message-ID | <i6au59Fe12eU22@mid.individual.net> |
| In reply to | #25900 |
On 14 Jan 2021 at 12:58:22 GMT, Daniel James <daniel@me.invalid> wrote: > In article <rtnhf6$gjc$1@dont-email.me>, The Natural Philosopher wrote: >>> Ah we have the solution - modulated X-Rays. >> >> well you may well laugh...why stop there. Gamma rays? > > You do know that X-Rays and Gamma rays are essentially the same thing? > > They occupy much the same part of the EM spectrum. The distinction > often made between them is to do with their means of production. Gamma > rays are produced inside the atomic nucleus while X-Rays are created by > relaxation of highly excited electrons outside the nucleus. > > https://en.wikipedia.org/wiki/X-ray#Gamma_rays Both are ionising, so can cause radiation damage. Gamma rays are much more energetic, however. Stuff like UV, visible light, and whatever 5G uses is not ionising. -- Tim
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2021-01-14 13:35 +0000 |
| Message-ID | <rtphbg$6b0$1@dont-email.me> |
| In reply to | #25900 |
On 14/01/2021 12:58, Daniel James wrote: > In article <rtnhf6$gjc$1@dont-email.me>, The Natural Philosopher wrote: >>> Ah we have the solution - modulated X-Rays. >> >> well you may well laugh...why stop there. Gamma rays? > > You do know that X-Rays and Gamma rays are essentially the same thing? > > They occupy much the same part of the EM spectrum. The distinction > often made between them is to do with their means of production. Gamma > rays are produced inside the atomic nucleus while X-Rays are created by > relaxation of highly excited electrons outside the nucleus. > > https://en.wikipedia.org/wiki/X-ray#Gamma_rays > Gamma rays are shorter waves than x rays.In my book. -- Future generations will wonder in bemused amazement that the early twenty-first century’s developed world went into hysterical panic over a globally average temperature increase of a few tenths of a degree, and, on the basis of gross exaggerations of highly uncertain computer projections combined into implausible chains of inference, proceeded to contemplate a rollback of the industrial age. Richard Lindzen
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| From | Scott Alfter <scott@alfter.diespammersdie.us> |
|---|---|
| Date | 2021-01-13 17:33 +0000 |
| Message-ID | <W9GLH.980$Ht5.235@fx36.iad> |
| In reply to | #25821 |
In article <rtmoi1$ofa$1@dont-email.me>, The Natural Philosopher <tnp@invalid.invalid> wrote: >My so called 72Mbps links couldn't handle HD TV, which is around 5Mbps I >think, reliably. Depends on the codecs involved. If you're slinging around MPEG-2 streams that were broadcast OTA, they could take up to 20 Mbps, though 8-12 for the primary stream is closer to typical. Years ago, I wanted to connect a MythTV backend over WiFi. 802.11g wouldn't cut it. There theoretically should've been enough bandwidth, but I think there was too much other nearby crap on the 2.4-GHz band that interfered. I was able to get decently reliable streaming of recorded TV when I switched to 802.11a, as hardly anybody else (and nobody nearby) was using 5 GHz at the time. _/_ / v \ Scott Alfter (remove the obvious to send mail) (IIGS( https://alfter.us/ Top-posting! \_^_/ >What's the most annoying thing on Usenet?
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| From | nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) |
|---|---|
| Date | 2021-01-13 16:22 +1300 |
| Message-ID | <2390112341@f420.n105.z1.binkp.net> |
| In reply to | #25821 |
TN> I now have an Ethernet cable to where the laptop lives I have a feeling that, in the end, this is gonna be the ticket. |07p|15AULIE|1142|07o |08.........
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| From | nospam.paul.lee@f420.n105.z1.binkp.net (paul lee) |
|---|---|
| Date | 2021-01-12 13:20 +1300 |
| Message-ID | <336738571@f420.n105.z1.binkp.net> |
| In reply to | #25777 |
CG> I had a T430 that died (very unusual for Lenovo T series), I now have CG> a T470 I bought used off eBay for rather less than I expected, lovely! I love the ThinkPad hardware; and while the T430/T440 series have SOME of the cool stuff from the old days, they are just beginning to be a little long in the tooth for me. I'm not very hardware intensive, but... I will be looking at some other ThinkPad models in the future. I might just bite the bullet and go CURRENT T-series, but I haven't decided just yet. CG> My WiFi connection reports that it is 300Mb/s but the real speed is CG> never anything like that. Here are my results sending from T470 CG> laptop (WiFi connection, reports as 300Mb/s) to desktop:- CG> CG> bone-debian-9.4-console-armhf-2018-07-08-1gb.img 100% CG> 850MB 16.2MB/s 00:52 CG> CG> So I get about half the 'expected' speed, also quite similar to your CG> speeds I think. Understood... however, you are getting a LITTLE better speeds than me; I wonder what type of WiFi chip/card is in the T470 vs what is CURRENT??? Maybe it would be worth it, for me, to upgrade the WiFi chip/card in my T430s to the best it will take, OR whatever is current in 2021... Even if I won't get the 100mb/s that I had THOUGHT, I'd probably see a better transfer rate anyway. Hmmmmm... I get around 80mb down on average, with my Thinkpad... |07p|15AULIE|1142|07o |08.........
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