zfs discuss - May 2010 - confused

did this come out?

http://cr.opensolaris.org/~gman/opensolaris-whats-new-2010-05/

i was googling trying to find info about the next release and ran across
this....


Does this mean it''s actually about to come out before the end of the
month
or is this something else?
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never mind....just found more info on this...shoudl have held back from
asking....


On Mon, May 24, 2010 at 1:26 AM, Thomas Burgess <wonslung at gmail.com>
wrote:
> did this come out?
>
> http://cr.opensolaris.org/~gman/opensolaris-whats-new-2010-05/
>
> i was googling trying to find info about the next release and ran across
> this....
>
>
> Does this mean it''s actually about to come out before the end of
the month
> or is this something else?
>
>
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Hi,

I have hit the synchronous NFS writing wall just like many people do.
There also have lots of discussion about the solutions here.
I want to post all of my exploring fighting done recently to discuss and share:

1): using the normal SATA-SSDs(intel/ocz) as ZIL device. For intel just EOLed
     50nm SSDs product line and the spec of the x25-M G2(34nm) 160G is getting
     more decent, I used this one. I get good performance boost compared with no
slog.
     I also manually did unplugging power server times, the outcome seems good 
-- I got
     no data corruption. But there is always potential risk - does it have
built-in ram cache?
We get no clear answer from intel.


2): using PCIE-SSD(i.e. fusionio''s ioDrive). For the universal standard
of PCIE-SSD is still on the way, the responding driver
     under solaris become apparent. And also the cost is very high.

3): using PCIE-DRAM-with(out)-SSD(i.e. marvell''s write acceleration
module (WAM), ddrdrive X1, curtisssd''s
   HyperCache. It has the higest spec but the same driver and high cost issue.

4): using SATA--DRAM-with(out)-SSD(i.e acard''s 9010,
curtisssd''s HyperHD). No driver issue and price is in the middle.
   I also tried acard 9010, the result is good enough.

So it seems we have to wait awhile to get a really ideal ZIL device solution. If
intel/ocz can confirm no ram cache, that will be good news.

Thanks.

Fred


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On 5/23/2010 11:30 PM, Fred Liu wrote:
>
> Hi,
>
> I have hit the synchronous NFS writing wall just like many people do.
>
> There also have lots of discussion about the solutions here.
>
> I want to post all of my exploring fighting done recently to discuss 
> and share:
>
> 1): using the normal SATA-SSDs(intel/ocz) as ZIL device. For intel 
> just EOLed
>
>      50nm SSDs product line and the spec of the x25-M G2(34nm) 160G is 
> getting
>
>      more decent, I used this one. I get good performance boost 
> compared with no slog.
>
>      I also manually did unplugging power server times, the outcome 
> seems good  -- I got
>
>      no data corruption. But there is always potential risk -- does it 
> have built-in ram cache?
>
> We get no clear answer from intel.
>
yes, both the X25-M (both G1 and G2) plus the X25-E have a DRAM buffer 
on the controller, and neither has a supercapacitor (or other battery) 
to back it up, so there is the potential for data loss (but /not/ data 
corruption) in a power-loss scenario.

Sadly, we''re pretty much at the point where no current retail-available
SSD has battery backup for it''s on-controller DRAM cache (and, they 
/all/ use DRAM caches).
> 2): using PCIE-SSD(i.e. fusionio''s ioDrive). For the universal 
> standard of PCIE-SSD is still on the way, the responding driver
>
>      under solaris become apparent. And also the cost is very high.
>
Yes, you do have to find those with Solaris drivers. Fortunately, pretty 
much all the manufacturers recognize the big market that ZFS/Solaris has 
for these devices, so most already have Solaris drivers, and the rest 
are almost universally working to produce them.
> 3): using PCIE-DRAM-with(out)-SSD(i.e. marvell''s write
acceleration
> module (WAM), ddrdrive X1, curtisssd''s
>
>    HyperCache. It has the higest spec but the same driver and high 
> cost issue.
>
Yup.
> 4): using SATA--DRAM-with(out)-SSD(i.e acard''s 9010,
curtisssd''s
> HyperHD). No driver issue and price is in the middle.
>
>    I also tried acard 9010, the result is good enough.
>
Frankly, these are about the best available solution, without breaking 
the bank. The bad news is that they''re not quite read-for-prime-time
yet
in terms of support and packaging.
> So it seems we have to wait awhile to get a really ideal ZIL device 
> solution. If intel/ocz can confirm no ram cache, that will be good news.
>
> Thanks.
>
> Fred
>
Nope, ALL SSDs use DRAM caches for their controllers. So far, I''m only 
aware that the Zeus stuff (plus a couple of industrial/military-only 
products) have battery backup for their controllers.  Idiots - it''s
like
$0.50 in parts, and a one-time $10,000 in engineer design/qa time to put 
the damned thing on, and they could charge a 25% premium and we''d pay
it.


Frankly, I''m really surprised that there''s no solution, given
that the
*amount* of NVRAM needed for ZIL (or similar usage) is really quite 
small. a dozen GB is more than sufficient, and really, most systems do 
fine with just a couple of GB (3-4 or so).  Producing a small, 
DRAM-based device in a 3.5" HD form-factor with built-in battery 
shouldn''t be hard, and I''m kinda flabberghasted nobody is
doing it.
Well, at least in the sub-$1000 category.  I mean, it''s 2 SODIMMs, a 
AAA-NiCad battery, a PCI-E->DDR2 memory controller, a PCI-E to SATA6Gbps 
controller, and that''s it.



-- 
Erik Trimble
Java System Support
Mailstop:  usca22-123
Phone:  x17195
Santa Clara, CA

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From: Erik Trimble [mailto:erik.trimble at oracle.com]
Sent: ??????, ???? 24, 2010 16:28
To: Fred Liu
Cc: ZFS Discussions
Subject: Re: [zfs-discuss] [ZIL device brainstorm] intel x25-M G2 has ram cache?

On 5/23/2010 11:30 PM, Fred Liu wrote:
Hi,

I have hit the synchronous NFS writing wall just like many people do.
There also have lots of discussion about the solutions here.
I want to post all of my exploring fighting done recently to discuss and share:

1): using the normal SATA-SSDs(intel/ocz) as ZIL device. For intel just EOLed
     50nm SSDs product line and the spec of the x25-M G2(34nm) 160G is getting
     more decent, I used this one. I get good performance boost compared with no
slog.
     I also manually did unplugging power server times, the outcome seems good 
-- I got
     no data corruption. But there is always potential risk ?C does it have
built-in ram cache?
We get no clear answer from intel.

yes, both the X25-M (both G1 and G2) plus the X25-E have a DRAM buffer on the
controller, and neither has a supercapacitor (or other battery) to back it up,
so there is the potential for data loss (but /not/ data corruption) in a
power-loss scenario.

Sadly, we''re pretty much at the point where no current retail-available
SSD has battery backup for it''s on-controller DRAM cache (and, they
/all/ use DRAM caches).


[Fred]: Yes. It is correct. I totally agree.




2): using PCIE-SSD(i.e. fusionio??s ioDrive). For the universal standard of
PCIE-SSD is still on the way, the responding driver
     under solaris become apparent. And also the cost is very high.

Yes, you do have to find those with Solaris drivers. Fortunately, pretty much
all the manufacturers recognize the big market that ZFS/Solaris has for these
devices, so most already have Solaris drivers, and the rest are almost
universally working to produce them.


[Fred]: Yes. Hope we can see the very first standard soon just like USB??


3): using PCIE-DRAM-with(out)-SSD(i.e. marvell??s write acceleration module
(WAM), ddrdrive X1, curtisssd??s
   HyperCache. It has the higest spec but the same driver and high cost issue.

Yup.



4): using SATA--DRAM-with(out)-SSD(i.e acard??s 9010, curtisssd??s HyperHD). No
driver issue and price is in the middle.
   I also tried acard 9010, the result is good enough.

Frankly, these are about the best available solution, without breaking the bank.
The bad news is that they''re not quite read-for-prime-time yet in terms
of support and packaging.

[Fred]: Agree.

So it seems we have to wait awhile to get a really ideal ZIL device solution. If
intel/ocz can confirm no ram cache, that will be good news.

Thanks.

Fred
Nope, ALL SSDs use DRAM caches for their controllers. So far, I''m only
aware that the Zeus stuff (plus a couple of industrial/military-only products)
have battery backup for their controllers.  Idiots - it''s like $0.50 in
parts, and a one-time $10,000 in engineer design/qa time to put the damned thing
on, and they could charge a 25% premium and we''d pay it.


Frankly, I''m really surprised that there''s no solution, given
that the *amount* of NVRAM needed for ZIL (or similar usage) is really quite
small. a dozen GB is more than sufficient, and really, most systems do fine with
just a couple of GB (3-4 or so).  Producing a small, DRAM-based device in a
3.5" HD form-factor with built-in battery shouldn''t be hard, and
I''m kinda flabberghasted nobody is doing it.  Well, at least in the
sub-$1000 category.  I mean, it''s 2 SODIMMs, a AAA-NiCad battery, a
PCI-E->DDR2 memory controller, a PCI-E to SATA6Gbps controller, and
that''s it.


[Fred]:  Agree. I am struggling so hard to procure that kind of device, but it
is so hard to find for an individual.


--

Erik Trimble

Java System Support

Mailstop:  usca22-123

Phone:  x17195

Santa Clara, CA
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> What you probably want is a motherboard which has a small area of main
> memory protected by battery, and a ramdisk driver which knows how to use
it.
> Then you''d get the 1,000,000 IOPS. No idea if anyone makes such a
thing.
> 
> You are correct that ZFS gets an enormous benefit from even tiny amounts if
> NV ZIL. Trouble is that no other operating systems or filesystems work this
> well with such relatively tiny amounts of NV storage, so such a hardware
> solution is very ZFS-specific.
No comment on how good or otherwise it is, but I just came across this:

http://www.ddrdrive.com/

Which appears to be looking to provide something for OpenSolaris...
(And some other minority interest OS called Windows).

Julian
--
Julian King
Computer Officer, University of Cambridge, Unix Support

Yeah, If plus the ability to backup the data to the BIOS/EPROM on the
motherboard, that should be the utmost solution?.

From: Andrew Gabriel [mailto:Andrew.Gabriel at oracle.com]
Sent: ???, ?? 24, 2010 18:37
To: Erik Trimble
Cc: Fred Liu; ZFS Discussions
Subject: Re: [zfs-discuss] [ZIL device brainstorm] intel x25-M G2 has ram cache?

Erik Trimble wrote:
Frankly, I''m really surprised that there''s no solution, given
that the *amount* of NVRAM needed for ZIL (or similar usage) is really quite
small. a dozen GB is more than sufficient, and really, most systems do fine with
just a couple of GB (3-4 or so).  Producing a small, DRAM-based device in a
3.5" HD form-factor with built-in battery shouldn''t be hard, and
I''m kinda flabberghasted nobody is doing it.  Well, at least in the
sub-$1000 category.  I mean, it''s 2 SODIMMs, a AAA-NiCad battery, a
PCI-E->DDR2 memory controller, a PCI-E to SATA6Gbps controller, and
that''s it.

It''s a bit of a wonky design. The DRAM could do something of the order
1,000,000 IOPS, and is then throttled back to a tiny fraction of that by the
SATA bottleneck. Disk interfaces like SATA/SAS really weren''t designed
for this type of use.

What you probably want is a motherboard which has a small area of main memory
protected by battery, and a ramdisk driver which knows how to use it. Then
you''d get the 1,000,000 IOPS. No idea if anyone makes such a thing.

You are correct that ZFS gets an enormous benefit from even tiny amounts if NV
ZIL. Trouble is that no other operating systems or filesystems work this well
with such relatively tiny amounts of NV storage, so such a hardware solution is
very ZFS-specific.
--
<http://www.oracle.com>[cid:image001.gif at
01CAFB70.D80EADB0]<http://www.oracle.com/><http://www.oracle.com>Andrew
Gabriel | Solaris Systems Architect
Email: andrew.gabriel at oracle.com<mailto:andrew.gabriel at oracle.com>
Mobile: +44 7720 598213<tel:+44%207720%20598213>
Oracle Pre-Sales
Guillemont Park | Minley Road | Camberley | GU17 9QG | United Kingdom

ORACLE Corporation UK Ltd is a company incorporated in England & Wales |
Company Reg. No. 1782505 | Reg. office: Oracle Parkway, Thames Valley Park,
Reading RG6 1RA
[cid:image002.gif at
01CAFB70.D80EADB0]<http://www.oracle.com/commitment>Oracle is committed to
developing practices and products that help protect the environment
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Yes. I mentioned this in my thread. And also I contacted Chris, ;-)

-----Original Message-----
From: zfs-discuss-bounces at opensolaris.org [mailto:zfs-discuss-bounces at
opensolaris.org] On Behalf Of J.P. King
Sent: ???, ?? 24, 2010 18:41
To: Andrew Gabriel
Cc: ZFS Discussions
Subject: Re: [zfs-discuss] [ZIL device brainstorm] intel x25-M G2 has ram cache?

> What you probably want is a motherboard which has a small area of main
> memory protected by battery, and a ramdisk driver which knows how to use
it.
> Then you''d get the 1,000,000 IOPS. No idea if anyone makes such a
thing.
> 
> You are correct that ZFS gets an enormous benefit from even tiny amounts if
> NV ZIL. Trouble is that no other operating systems or filesystems work this
> well with such relatively tiny amounts of NV storage, so such a hardware
> solution is very ZFS-specific.
No comment on how good or otherwise it is, but I just came across this:

http://www.ddrdrive.com/

Which appears to be looking to provide something for OpenSolaris...
(And some other minority interest OS called Windows).

Julian
--
Julian King
Computer Officer, University of Cambridge, Unix Support
_______________________________________________
zfs-discuss mailing list
zfs-discuss at opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

On May 24, 2010, at 4:28 AM, Erik Trimble wrote:
> yes, both the X25-M (both G1 and G2) plus the X25-E have a DRAM buffer on
the controller, and neither has a supercapacitor (or other battery) to back it
up, so there is the potential for data loss (but /not/ data corruption) in a
power-loss scenario.
> 
> Sadly, we''re pretty much at the point where no current
retail-available SSD has battery backup for it''s on-controller DRAM
cache (and, they /all/ use DRAM caches).
I haven''t seen where anyone has tested this, but the MemoRight SSD
(sold by RocketDisk in the US) seems to claim all the right things:

http://www.rocketdisk.com/vProduct.aspx?ID=1

pdf specs:

http://www.rocketdisk.com/Local/Files/Product-PdfDataSheet-1_MemoRight%20SSD%20GT%20Specification.pdf

They claim to support the cache flush command, and with respect to DRAM cache
backup they say (p. 14/section 3.9 in that pdf):
> The MemoRight?s NSSD have an on-drive backup power system. It saves energy
when the power supply is applied to drive. When power-off occurring, the saved
energy will be released to keep the drive working for a while. The saved energy
ensures the data in the cache can be flushed to the nonvolatile flash media,
which prevents the data loss to happen.
> It will take about 5 seconds to save enough energy for discharge at lease 1
second. The write cache will be disabled automatically before the backup power
system saved enough energy.
Which certainly sounds like an on-board capacitor to flush the cache and that
the cache is disabled while charging the capacitor.  But I can''t see
where anyone has tested this on ZFS.

--Ware

Yeah. It is also not so easy to capture the possible data loss during.
There is no reliable way to figure it out.

Thanks.

Fred.

-----Original Message-----
From: rwalists at washdcmail.com [mailto:rwalists at washdcmail.com] 
Sent: ???, ?? 25, 2010 11:42
To: Erik Trimble
Cc: Fred Liu; ZFS Discussions
Subject: Re: [zfs-discuss] [ZIL device brainstorm] intel x25-M G2 has ram cache?

On May 24, 2010, at 4:28 AM, Erik Trimble wrote:
> yes, both the X25-M (both G1 and G2) plus the X25-E have a DRAM buffer on
the controller, and neither has a supercapacitor (or other battery) to back it
up, so there is the potential for data loss (but /not/ data corruption) in a
power-loss scenario.
> 
> Sadly, we''re pretty much at the point where no current
retail-available SSD has battery backup for it''s on-controller DRAM
cache (and, they /all/ use DRAM caches).
I haven''t seen where anyone has tested this, but the MemoRight SSD
(sold by RocketDisk in the US) seems to claim all the right things:

http://www.rocketdisk.com/vProduct.aspx?ID=1

pdf specs:

http://www.rocketdisk.com/Local/Files/Product-PdfDataSheet-1_MemoRight%20SSD%20GT%20Specification.pdf

They claim to support the cache flush command, and with respect to DRAM cache
backup they say (p. 14/section 3.9 in that pdf):
> The MemoRight?s NSSD have an on-drive backup power system. It saves energy
when the power supply is applied to drive. When power-off occurring, the saved
energy will be released to keep the drive working for a while. The saved energy
ensures the data in the cache can be flushed to the nonvolatile flash media,
which prevents the data loss to happen.
> It will take about 5 seconds to save enough energy for discharge at lease 1
second. The write cache will be disabled automatically before the backup power
system saved enough energy.
Which certainly sounds like an on-board capacitor to flush the cache and that
the cache is disabled while charging the capacitor.  But I can''t see
where anyone has tested this on ZFS.

--Ware

--On 24 May 2010 23:41 -0400 rwalists at washdcmail.com wrote:
> I haven''t seen where anyone has tested this, but the MemoRight SSD
(sold
> by RocketDisk in the US) seems to claim all the right things:
>
> http://www.rocketdisk.com/vProduct.aspx?ID=1
>
> pdf specs:
>
> http://www.rocketdisk.com/Local/Files/Product-PdfDataSheet-1_MemoRight%20
> SSD%20GT%20Specification.pdf
>
> They claim to support the cache flush command, and with respect to DRAM
> cache backup they say (p. 14/section 3.9 in that pdf):
At the risk of this getting a little off-topic (but hey, we''re all
looking
for ZFS ZIL''s ;) We''ve had similar issues when looking at
SSD''s recently
(lack of cache protection during power failure) - the above SSD''s look 
interesting [finally someone''s noted you need to protect the cache] -
but
from what I''ve read about the Intel X25-E performance - the Intel drive
with write cache turned off appears to be as fast, if not faster than those 
drives anyway...

I''ve tried contacting Intel to find out if it''s true their
"enterprise" SSD
has no cache protection on it, and what the effect of turning the write 
cache off would have on both performance and write endurance, but not heard 
anything back yet.

Picking apart the Intel benchmarks published - they always have the 
write-cache enabled, which probably speaks volumes...

-Karl

On Tue, May 25, 2010 at 10:08:57AM +0100, Karl Pielorz
wrote:
>
>
> --On 24 May 2010 23:41 -0400 rwalists at washdcmail.com wrote:
>
>> I haven''t seen where anyone has tested this, but the MemoRight
SSD (sold
>> by RocketDisk in the US) seems to claim all the right things:
>>
>> http://www.rocketdisk.com/vProduct.aspx?ID=1
>>
>> pdf specs:
>>
>>
http://www.rocketdisk.com/Local/Files/Product-PdfDataSheet-1_MemoRight%20
>> SSD%20GT%20Specification.pdf
>>
>> They claim to support the cache flush command, and with respect to DRAM
>> cache backup they say (p. 14/section 3.9 in that pdf):
>
> At the risk of this getting a little off-topic (but hey, we''re all
> looking for ZFS ZIL''s ;) We''ve had similar issues when
looking at SSD''s
> recently (lack of cache protection during power failure) - the above 
> SSD''s look interesting [finally someone''s noted you need
to protect the
> cache] - but from what I''ve read about the Intel X25-E performance
- the
> Intel drive with write cache turned off appears to be as fast, if not 
> faster than those drives anyway...
>
> I''ve tried contacting Intel to find out if it''s true
their "enterprise"
> SSD has no cache protection on it, and what the effect of turning the 
> write cache off would have on both performance and write endurance, but 
> not heard anything back yet.
>
I guess the problem is not the cache by itself, but the fact that they
ignore the CACHE FLUSH command.. and thus the non-battery-backed cache
becomes a problem.

-- Pasi
> Picking apart the Intel benchmarks published - they always have the  
> write-cache enabled, which probably speaks volumes...
>
> -Karl
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss at opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

--On 25 May 2010 15:28 +0300 Pasi K?rkk?inen <pasik at iki.fi> wrote:
>> I''ve tried contacting Intel to find out if it''s true
their "enterprise"
>> SSD has no cache protection on it, and what the effect of turning the
>> write cache off would have on both performance and write endurance, but
>> not heard anything back yet.
>>
>
> I guess the problem is not the cache by itself, but the fact that they
> ignore the CACHE FLUSH command.. and thus the non-battery-backed cache
> becomes a problem.
The X25-E''s do apparently honour the ''Disable Write
Cache'' command -
without write cache, there is no cache to flush - all data is written to 
flash immediately - presumably before it''s ACK''d to the host.

I''ve seen a number of other sites do some testing with this - and found
that it ''works'' (i.e. with write-cache enabled, you get nasty
data loss if
the power is lost - with it disabled, it closes that window). But you 
obviously take quite a sizeable performance hit.

We''ve got an X25-E here which we intend to test for ourselves (wisely
;) -
to make sure that is the case...

-Karl

On Tue, May 25, 2010 at 01:52:47PM +0100, Karl Pielorz
wrote:
>
> --On 25 May 2010 15:28 +0300 Pasi K?rkk?inen <pasik at iki.fi> wrote:
>
>>> I''ve tried contacting Intel to find out if it''s
true their "enterprise"
>>> SSD has no cache protection on it, and what the effect of turning
the
>>> write cache off would have on both performance and write endurance,
but
>>> not heard anything back yet.
>>>
>>
>> I guess the problem is not the cache by itself, but the fact that they
>> ignore the CACHE FLUSH command.. and thus the non-battery-backed cache
>> becomes a problem.
>
> The X25-E''s do apparently honour the ''Disable Write
Cache'' command -
> without write cache, there is no cache to flush - all data is written to  
> flash immediately - presumably before it''s ACK''d to the
host.
>
> I''ve seen a number of other sites do some testing with this - and
found
> that it ''works'' (i.e. with write-cache enabled, you get
nasty data loss
> if the power is lost - with it disabled, it closes that window). But you  
> obviously take quite a sizeable performance hit.
>
Yeah.. what I meant is: if you have write cache enabled, and the ssd drive
honours ''CACHE FLUSH'' command, then you should be safe.. 

Based on what I''ve understood the Intel SSDs ignore the CACHE FLUSH
command,
and thus it''s not safe to run them with caches enabled..
> We''ve got an X25-E here which we intend to test for ourselves
(wisely ;)
> - to make sure that is the case...
>
Please let us know how it goes :)

-- Pasi

On Tue, 25 May 2010, Karl Pielorz wrote:
>
> The X25-E''s do apparently honour the ''Disable Write
Cache'' command - without
> write cache, there is no cache to flush - all data is written to flash 
> immediately - presumably before it''s ACK''d to the host.
There is always a cache, even if it is just a 4K working buffer 
representing one SSD erasure block.

Bob
-- 
Bob Friesenhahn
bfriesen at simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/

On Tue, May 25, 2010 at 2:08 AM, Karl Pielorz <kpielorz_lst at tdx.co.uk>
wrote:
> I''ve tried contacting Intel to find out if it''s true
their "enterprise" SSD
> has no cache protection on it, and what the effect of turning the write
The "E" in X25-E does not mean "enterprise". It means
"extreme". Like
the "EE" series CPUs that Intel offers.

-B

-- 
Brandon High : bhigh at freaks.com

--On 25 May 2010 11:15 -0700 Brandon High <bhigh at freaks.com> wrote:
> On Tue, May 25, 2010 at 2:08 AM, Karl Pielorz <kpielorz_lst at
tdx.co.uk>
> wrote:
>> I''ve tried contacting Intel to find out if it''s true
their "enterprise"
>> SSD has no cache protection on it, and what the effect of turning the
>> write
>
> The "E" in X25-E does not mean "enterprise". It means
"extreme". Like
> the "EE" series CPUs that Intel offers.
Yet most of their web site seems to aim it quite firmly at the
''Enterprise''
market, "Imagine replacing up to 50 high-RPM hard disk drives with one 
Intel? X25-E Extreme SATA Solid-State Drive in your servers" or, 
"Enterprise applications place a premium on performance, reliability, power
consumption and space."

If you don''t mind a little data loss risk? :)

I''ll post back when we''ve had a chance to try one in the
''real world'' for
our applications - with and without caching, especially when the plug gets 
pulled :)

Otherwise, at least on the surface the quest for the ''perfect''
(performance, safety, price, size) ZIL continues...

-Karl