On Wed, Nov 15, 2000 at 02:01:28PM +0100, Borut Mrak wrote:
> On Wed, Nov 15, 2000 at 01:44:25PM +0100, Bosnjak Zoran RDVV wrote:
> > Zanima me, katere kartice kupiti in koliko je najvec N pri /dev/ethN.
> Zdaj pa k mojemu vprasanju: Ali ima kdo izkusnje s tremi rtl8139 karticami
> v enem racunalniku? Kernel 2.4.0-test10 ima namesto Beckerjevega rtl8139
> gonilnika 8139too, ki ga je napisal nekdo pri Mandrake-u. Na zalost zadeva
> po defaultu prepozna le dve mrezni kartici, brskanje po sourcu pa mi ni
> pomagalo prav dosti, prav tako ne direktorij Documentation.
rtl8139 driver dela super z geniusovimi hubkarticami (vsaka ima 4
ethernet porte), nisem pa se se srecal z masino, ki bi imela vec
takih kartic (ker ena stane ~30k si jih vec ne morem privoscit :),
imam pa masino z vec rtl8139 karticami, ki skupaj delujejo super.
Notri so stiri rtl8139 in ena rtl8029. Po mojem bodo tudi hubkartice
podobno dobro funkcionirale.
Ce imas 5 pci slotov, potem je to ze 20 ethernet portov, whoa :) Dober
switch (no ja, niti ne, 200MHz procesor bo ob 100Mbps prometu ze precej
hudo obremenjen, nikakor pa si ne smes privoscit vkljucit "fast packet
switching" v kernelu, ker se bo procesor zadavil).
Se nekaj: Te kartice (rtl8139) niso najboljse. V izvorni kodi gonilnika
je opisano, cemu niso optimalne za uporabo pod linuxom:
[iz rtl8139.c:]
III. Driver operation
IIIa. Rx Ring buffers
The receive unit uses a single linear ring buffer rather than the more
common (and more efficient) descriptor-based architecture. Incoming frames
are sequentially stored into the Rx region, and the host copies them into
skbuffs.
Comment: While it is theoretically possible to process many frames in place,
any delay in Rx processing would cause us to drop frames. More importantly,
the Linux protocol stack is not designed to operate in this manner.
IIIb. Tx operation
The RTL8129 uses a fixed set of four Tx descriptors in register space.
In a stunningly bad design choice, Tx frames must be 32 bit aligned. Linux
aligns the IP header on word boundaries, and 14 byte ethernet header means
that almost all frames will need to be copied to an alignment buffer.
[snip]
Skratka, kartice niso najbolje zgrajene. Ce imas denar, kupi kaj boljsega.
Alternativa so kaksne druge hub kartice, vendar jih jaz se nisem videl.
Najboljsi driverji (po mojih izkusnjah) so eepro100, de4x5 in via-rhine,
ter driver za compaqov turbolan (tlan). via-rhine deluje z nekim via
chipsetom (pise v driverjevi dokumentaciji) ki ga imam na nekaj d-linkovih
10/100M karticah in deluje presenetljivo dobro.
Aja, vse to deluje v 100M half duplex nacinu in zdrzi poln promet, razen
v enem primeru, ko je motherboard popolnoma zanic :) Iste kartice v drugi
masini z drugacnim motherboardom in *enakim* kernelom delujejo super.
Zdaj sem pa ze prevec napisal :)
--
Jure Koren | unix administrator
[EMAIL PROTECTED] | gnu/Linux software developer
