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Topic: Forced Write = Off

All greetings. The people prompt, at me high intensity of insert queries and update of the data in DB Firebird 2.5 64-bit Classic and I think to install mode Forced Writes at a database in OFF, read that it increases speed of write operations to 3 time. Who  tried to disconnect Forced Write?

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Re: Forced Write = Off

Sol87;
Well if to you spit on safety of a DB you can to disconnect.
If is not present it is necessary to search for other ways of optimization

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Re: Forced Write = Off

Sol87 wrote:

Who  tried to disconnect Forced Write?

Yes, tried so to do on steam of branches, yes works noticeably faster, depends on many criteria how much faster. Yes, in case of problems with an electricity the basis falls, and it too happened. But since basis filial it basically is recovered from center, and, yes recovered. It is leveled by switching-on  cachings on  the controler, it is safe, but it is required . The equipment.
Therefore the general recommendation for test DB and bases of purely storable aggregates it is possible to make asynchronous record, for  bases only the synchronous record and  an array  which can " the brains" and write .

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Re: Forced Write = Off

Sol87 wrote:

All greetings. The people prompt, at me high intensity of insert queries and update of the data in DB Firebird 2.5 64-bit Classic and I think to install mode Forced Writes at a database in OFF, read that it increases speed of write operations to 3 time. Who  tried to disconnect Forced Write?

If the server on the UPS with appropriate service, problems should not be.

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Re: Forced Write = Off

rdb_dev, we admit there is an appropriate UPS if I disconnect Forced Writes the changed pages are in an operating system cache until the operating system does not decide to write down them on a disk. Can be such that by the continuous operation from a DB the operating system can not drop the changed pages on a disk until all users not to be disconnected from a database. To what that can check in the image write process on a disk?

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Re: Forced Write = Off

There can be everything. It is impossible to check.

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Re: Forced Write = Off

More truly, it is possible to affect (through configs MaxUnflushed *);
But it is impossible to check all the same, AFAIU.

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Re: Forced Write = Off

Sol87 wrote:

to What that can check in the image write process on a disk?

What for to you it to supervise?

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Re: Forced Write = Off

rdb_dev, well or it is possible to adjust, that the data registered in a disk during certain time, or through what that a time interval.

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Re: Forced Write = Off

Sol87> to adjust, that the data registered in a disk
Sol87> during certain time, or through what that a time interval.
I just above prompted . Options in a config.
It is possible to adjust time and-or an amount.

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Re: Forced Write = Off

Sol87 wrote:

All greetings. The people prompt, at me high intensity of insert queries and update of the data in DB Firebird 2.5 64-bit Classic and I think to install mode Forced Writes at a database in OFF, read that it increases speed of write operations to 3 time. Who  tried to disconnect Forced Write?

Is better write that for intensity (how many requests in a minute) and that for the equipment, what disk subsystem.
Each request in the transaction? Or packs?
Parameters in requests are used?
Etc. etc.

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Re: Forced Write = Off

Gadzhimuradov Rustam, sorry, saw not at once your record.

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Re: Forced Write = Off

Sol87 wrote:

rdb_dev, well or it is possible to adjust, that the data registered in a disk during certain time, or through what that a time interval.

Also what it gives to you?  these dancings?

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Re: Forced Write = Off

rdb_dev wrote:

If the server on the UPS with appropriate service, problems should not be.

Problems will be. As a variant (was at us): the server works, the electricity goes out, he any time works, automatics works, the server receives a command on  the UPS-server and correctly dies away. There is light, but batteries yet did not type completely a charge, but the server already , light again goes out and  any more does not suffice to go out correctly. Greetings  basis.
It would be desirable the guaranteed result only the synchronous record at level , it is asynchronously possible to write "more deeply" at level , everything there is for this purpose provided that is required for safe operation.

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Re: Forced Write = Off

Ivan_Pisarevsky wrote:

it any time works

Here this superfluous.

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Re: Forced Write = Off

Ivan_Pisarevsky wrote:

it is passed...
Problems will be. As a variant (was at us): the server works, the electricity goes out, he any time works, automatics works, the server receives a command on  the UPS-server and correctly dies away. There is light, but batteries yet did not type completely a charge, but the server already , light again goes out and  any more does not suffice to go out correctly. Greetings  basis.

your UPS, most likely, was . I even on house APC Smart-UPS SUA1000I have the adjustment of the UPS setting percent of a charge of batteries, at which UPS submits output pressure at renewal of input pressure. I Will arrive home, I can look more in detail.

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Re: Forced Write = Off

WildSery wrote:

it is passed...
Here this superfluous.

you Offer on each miss of light for a minute there and then all to extinguish? And to work when? Light at us blinks regularly and  on workplaces is not simple so, 9 from such 10 blinkings do not lead to stops in operation.

rdb_dev wrote:

your UPS, most likely, was . I even on house APC Smart-UPS SUA1000I have the adjustment of the UPS setting percent of a charge of batteries, at which UPS submits output pressure at renewal of input pressure. I Will arrive home, I can look more in detail.

It it would be necessary to puzzle the administrator, it is not eliminated, by the way.

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Re: Forced Write = Off

Ivan_Pisarevsky;
[spoiler Power Failure settings for APC Smart-UPS] [img=https://lh3.googleusercontent.com/-MOoBdqgwXsQ/WblUqYP2bJI/AAAAAAAAACc/2AvuqZ_L-EIlRghLn7WSdwPPxpewF1QGACJoC/w530-h472-n/sua1000i.jpg] [/spoiler]
The moderator: Nesting is remote.

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Re: Forced Write = Off

Sol87 wrote:

All greetings. The people prompt, at me high intensity of insert queries and update of the data in DB Firebird 2.5 64-bit Classic and I think to install mode Forced Writes at a database in OFF, read that it increases speed of write operations to 3 time. Who  tried to disconnect Forced Write?

if to make spot-check from SSD, speed increases in much more time, at smaller risk.

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Re: Forced Write = Off

Ivan_Pisarevsky wrote:

you Offer on each miss of light for a minute there and then all to extinguish? And to work when? Light at us blinks regularly and  on workplaces is not simple so, 9 from such 10 blinkings do not lead to stops in operation.

Here it is necessary to consider, how many holds the UPS of everything, what is the time occupies server shatdaun/start, UPS charging what is the time occupies.
If time server start-stop is rather insignificant, UPS charging slow, and light goes out often yes, through pair minutes to extinguish. As 5 starts-stops take away less time, than server operation for 10 minutes longer, but then waiting of charging of the UPS to comprehensible level.

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Re: Forced Write = Off

NTFS
[quote =] To ensure that the right amount of flushing occurs, the cache manager spawns a process every second called a lazy writer. The lazy writer process queues one-eighth of the pages that have not been flushed recently to be written to disk.