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Home - General / All posts - Performance effects of Meltdown and Spectre mitigations

7,602 post(s)
#12-Jan-18 00:57

Providers are falling over themselves to work around the speculative execution bugs announced a week or so ago.

Supposedly full patches are now available for some systems, including Windows patches for Meltdown and CPU microcode revisions to reduce vulnerability to Spectre. (How far back the microcode revisions will stretch seems an open question so far.)

Only one of my systems so far has the full set (an HP ZBook 15). Before I update it I thought I should run some Manifold 9 tests, to compare performance afterwards to see how deeply the Radian engine is affected.

So this is a bookmark for results, and also a suggestion in case anyone else wants to do the same.

We could test some transport-heavy queries (a simple UPDATE, say, and a SELECT INTO using GROUP and/or CASE) as well as some heavier geometry work that utilises multiple threads.

If I sort out some suitable test data and queries (that's the intention) then I'll post them here.


7,602 post(s)
#13-Jan-18 13:50

Best explanation of Meltdown and Spectre I have read so far is by Peter Bright in Ars Technica.


7,444 post(s)
#14-Jan-18 09:39

A more technical explanation:

Reading privileged memory with a side-channel


7,444 post(s)
#14-Jan-18 09:36

These attacks are truly next-level. The implications from the fixes are pretty horrible and the performance is only part of the picture.

There is a bit of a bright spot in that the attacker has to research what it attacks extensively and he has to work with the constraints of the attacked code. This takes time and effort and the success is not guaranteed. Furthermore, patches and updates erase a significant part or even all of the work put into creating an attack. This should limit feasible targets of these attacks significantly (basically to the OSes - which are already being patched, and to the most popular versions of the most popular apps = browsers - which are starting to take measures against the attacks as well).

249 post(s)
#14-Jan-18 17:07

ALL pc layers are concern even the main problem is the CPU/architecture/manufacturer ( intel AMD ARM qualcomm...)

article for consumer :


0) clound service

use patch from OS, cpu

amazon aws EC2

azure office 365

1)browser ( site isolation)


chromium base wait 23 january the new 63 version so for now use chrome://flags/#enable-site-per-process then enable restart


Microsot edge

webkit ( safari)

2) OS

Microsoft OS use powwershell



red hat

2) motherboard

msinfo32 ll give us the name of motherboard





--Phoenix Technologies



5) CPU




NB color support in edit mode not in view mode

chrome_Speculative Execution_site_isolation.png
windows10_Speculative Execution_powershell.png

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