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 Fri, 10 Jul 2020 23:31:24 +0300 (MSK)
References: <20200710075605.217824-1-gorcunov@gmail.com>
 <20200710075605.217824-2-gorcunov@gmail.com>
From: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
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Date: Fri, 10 Jul 2020 22:31:22 +0200
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Subject: Re: [Tarantool-patches] [PATCH 1/5] qsync: eliminate redundant
	writes
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To: Cyrill Gorcunov <gorcunov@gmail.com>, tml <tarantool-patches@dev.tarantool.org>

Hi!

On 10/07/2020 09:56, Cyrill Gorcunov wrote:
> Instead of updating is_sync variable on every
> cycle write it once.
> 
> Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
> ---
>  src/box/txn.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/src/box/txn.c b/src/box/txn.c
> index a2df23833..49b2b2649 100644
> --- a/src/box/txn.c
> +++ b/src/box/txn.c
> @@ -567,8 +567,12 @@ txn_journal_entry_new(struct txn *txn)
>  		if (stmt->row == NULL)
>  			continue;
>  
> -		is_sync = is_sync || (stmt->space != NULL &&
> -				      stmt->space->def->opts.is_sync);
> +		if (!is_sync) {
> +			if (stmt->space != NULL &&
> +			    stmt->space->def->opts.is_sync) {
> +				is_sync = true;
> +			}
> +		}
>  
>  		if (stmt->row->replica_id == 0)
>  			*local_row++ = stmt->row;

The 'redundant' writes were done intentionally, to avoid unnecessary
branching. I see no point in this change.