It's quieter these days from 10.30am-1.20pm - US treasury open, London time in eurex bonds but there's always exceptions. I'd say 12-1pm is lunch down time (1pm to 2pm CET) after which the Americans start getting involved and first round of their figures at half past. Remember a big chunk of the European trade is done from London so their break has the noticeable impact.
You mean the traders trading Bund or DAX/stoxx also come from London? I think Bund and DAX have huge volume and mainly from Germany.
yes, the volume is very low on a Bank holiday but people said those guys or companys trading bund are using Auto systems, they can trade all the times , can't they?
Banks or inter-broker dealers use auto systems to disguise and efficiently execute large paper orders for clients such as pension funds with real needs such as month end duration extensions. If there are no orders coming through to the bank's brokers there's nothing to feed into the algo to execute. If the volumes are low on a UK bank holiday because brokers like a day off why would you execute your big order into a thin market even through an algo? If you are referring to algos that scalp for locals or boutiques then yes they are active but without any paper orders to move the market it's just machines churning against other machines or locals. So over a UK bank holiday the volume is very low. With London the financial trading centre of Europe and FX volume capital of the world, when they have a day off or hour off it's noticed for the reasons above. Even someone like Prague based http://www.rsj.com/en/ will be wary of London having a day off.
Thing slow up about 8:30 am pacific time most days... in fact they get kind of dramatic leading up to 8:30 sometimes...